gh-108303: Move zip and tar archives to Lib/test/archivetestdata (#111549)

Author: sobolevn

Lib/test/ziptestdata/README.md renamed to Lib/test/archivetestdata/README.md

@@ -1,29 +1,31 @@
-# Test data for `test_zipfile`
+# Test data for `test_zipfile`, `test_tarfile` (and even some others)
 
-The test executables in this directory are created manually from header.sh and
+## `test_zipfile`
+
+The test executables in this directory are created manually from `header.sh` and
 the `testdata_module_inside_zip.py` file.  You must have Info-ZIP's zip utility
 installed (`apt install zip` on Debian).
 
-## Purpose
+### Purpose of `exe_with_zip` and `exe_with_z64`
 
 These are used to test executable files with an appended zipfile, in a scenario
 where the executable is _not_ a Python interpreter itself so our automatic
 zipimport machinery (that'd look for `__main__.py`) is not being used.
 
-## Updating the test executables
+### Updating the test executables
 
 If you update header.sh or the testdata_module_inside_zip.py file, rerun the
 commands below.  These are expected to be rarely changed, if ever.
 
-### Standard old format (2.0) zip file
+#### Standard old format (2.0) zip file
 
 ```
 zip -0 zip2.zip testdata_module_inside_zip.py
 cat header.sh zip2.zip >exe_with_zip
 rm zip2.zip
 ```
 
-### Modern format (4.5) zip64 file
+#### Modern format (4.5) zip64 file
 
 Redirecting from stdin forces Info-ZIP's zip tool to create a zip64.
 
@@ -32,4 +34,3 @@ zip -0 <testdata_module_inside_zip.py >zip64.zip
 cat header.sh zip64.zip >exe_with_z64
 rm zip64.zip
 ```
-