gh-36999: Rename `install-requires.txt` to `version_requirements.txt`
    
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As discussed in #36982:
- the name "install-requires"  has become outdated with the transition
to the new names set by the `pyproject.toml` format (see https://setupto
ols.pypa.io/en/latest/userguide/dependency_management.html#declaring-
required-dependency, compare the tabs "pyproject.toml" vs. "setup.cfg")
- this will help with #35890, as
GitHub will be able to just read the `version_requirements.txt` files

#36982 (comment)

Notes for reviewers:
- **This is a simple, limited-scope improvement and not intended as a
long-term commitment to the format of the files in build/pkgs/....**
- PRs #37430, #37350, #36740 remove direct access to build/pkgs in favor
of using the sage_bootstrap API (sage --package).

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### ⌛ Dependencies

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- Depends on #37401

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URL: #36999
Reported by: Matthias Köppe
Reviewer(s): Dima Pasechnik, Kwankyu Lee, Nathan Dunfield

Author: Release Manager

Makefile

@@ -343,15 +343,15 @@ CONFIGURE_DEPENDENCIES =							\
 	build/pkgs/*/spkg-configure.m4						\
 	build/pkgs/*/type build/pkgs/*/SPKG.rst					\
 	build/pkgs/*/checksums.ini build/pkgs/*/requirements.txt		\
-	build/pkgs/*/install-requires.txt build/pkgs/*/package-version.txt	\
+	build/pkgs/*/version_requirements.txt build/pkgs/*/package-version.txt	\
 	build/pkgs/*/spkg-install build/pkgs/*/spkg-install.in
 
 # SPKG_INFO_DEPENDENCIES is the list of files that influence the run of 'sage-spkg-info' and hence
 # the generation of the files generated in 'src/doc' by 'src/doc/bootstrap'.
 SPKG_INFO_DEPENDENCIES =							\
 	build/pkgs/*/type build/pkgs/*/SPKG.rst					\
 	build/pkgs/*/requirements.txt						\
-	build/pkgs/*/install-requires.txt build/pkgs/*/package-version.txt	\
+	build/pkgs/*/version_requirements.txt build/pkgs/*/package-version.txt	\
 	build/pkgs/*/distros/*.txt
 
 configure: bootstrap src/doc/bootstrap $(CONFIGURE_DEPENDENCIES) $(SPKG_INFO_DEPENDENCIES)

bootstrap

@@ -105,7 +105,7 @@ EOF
             SPKG_TREE_VAR="$(sed "s/#.*//;" "$DIR/trees.txt")"
         else
             SPKG_TREE_VAR=SAGE_LOCAL
-            if test -f "$DIR/requirements.txt" -o -f "$DIR/install-requires.txt"; then
+            if test -f "$DIR/requirements.txt" -o -f "$DIR/version_requirements.txt"; then
                 # A Python package
                 SPKG_TREE_VAR=SAGE_VENV
                 echo "define(>>>SPKG_INSTALL_REQUIRES_${pkgname}<<<, >>>$(echo $(sage-get-system-packages install-requires ${pkgname}))<<<)dnl" >> m4/sage_spkg_versions.m4

bootstrap-conda

@@ -132,11 +132,11 @@ echo >&2 $0:$LINENO: generate conda environment files
     (
         echo >&4 "  - pip:"
         echo >&5 "  - pip:"
-        for PKG_BASE in $(sage-package list :standard: :optional: --has-file requirements.txt --no-file distros/conda.txt --no-file src; sage-package list :standard: :optional: --has-file install-requires.txt --no-file requirements.txt --no-file distros/conda.txt --no-file src); do
+        for PKG_BASE in $(sage-package list :standard: :optional: --has-file requirements.txt --no-file distros/conda.txt --no-file src; sage-package list :standard: :optional: --has-file version_requirements.txt --no-file requirements.txt --no-file distros/conda.txt --no-file src); do
             PKG_SCRIPTS=build/pkgs/$PKG_BASE
             SYSTEM_PACKAGES_FILE=$PKG_SCRIPTS/requirements.txt
             if [ ! -f $SYSTEM_PACKAGES_FILE ]; then
-                SYSTEM_PACKAGES_FILE=$PKG_SCRIPTS/install-requires.txt
+                SYSTEM_PACKAGES_FILE=$PKG_SCRIPTS/version_requirements.txt
             fi
             PKG_TYPE=$(cat $PKG_SCRIPTS/type)
             if grep -q SAGERUNTIME $PKG_SCRIPTS/dependencies $PKG_SCRIPTS/dependencies_order_only 2>/dev/null; then

build/bin/sage-get-system-packages

@@ -14,21 +14,21 @@ fi
 
 case "$SYSTEM" in
     install-requires)
-        # Collect install-requires.txt (falling back to requirements.txt) and output it in the format
-        # needed by setup.cfg [options] install_requires=
-        SYSTEM_PACKAGES_FILE_NAMES="install-requires.txt requirements.txt"
+        # Collect version_requirements.txt (falling back to requirements.txt) and output it in the format
+        # needed by setup.cfg [options] version_requirements=
+        SYSTEM_PACKAGES_FILE_NAMES="version_requirements.txt requirements.txt"
         STRIP_COMMENTS="sed s/#.*//;/^[[:space:]]*$/d;"
         COLLECT=
         ;;
     install-requires-toml)
-        # Collect install-requires.txt (falling back to requirements.txt) and output it in the format
+        # Collect version_requirements.txt (falling back to requirements.txt) and output it in the format
         # needed by pyproject.toml [build-system] requires=
-        SYSTEM_PACKAGES_FILE_NAMES="install-requires.txt requirements.txt"
+        SYSTEM_PACKAGES_FILE_NAMES="version_requirements.txt requirements.txt"
         STRIP_COMMENTS="sed s/#.*//;/^[[:space:]]*$/d;s/^/'/;s/$/',/;"
         COLLECT=
         ;;
     pip)
-        SYSTEM_PACKAGES_FILE_NAMES="requirements.txt install-requires.txt"
+        SYSTEM_PACKAGES_FILE_NAMES="requirements.txt version_requirements.txt"
         STRIP_COMMENTS='sed s/#.*//;s/[[:space:]]//g;'
         COLLECT=echo
         ;;

build/bin/sage-spkg-info

@@ -54,7 +54,7 @@ echo
 echo "Version Information"
 echo "-------------------"
 echo
-for a in package-version.txt requirements.txt install-requires.txt; do
+for a in package-version.txt requirements.txt version_requirements.txt; do
     if [ -f "$PKG_SCRIPTS"/"$a" ]; then
         echo "$a::"
         echo