Revert "simplify .gitattributes"

This reverts commit a75e970.

That change to `.gitattributes`, though intended as a refactoring,
caused the currently committed generated archives not to be able to
be used, producing Windows `test-fast` failures similar to #1358.

See comments in #1607 for details.

.gitattributes

@@ -1,11 +1,11 @@
-generated-archives/*.tar* filter=lfs-disabled diff=lfs merge=lfs -text
+**/generated-archives/*.tar* filter=lfs-disabled diff=lfs merge=lfs -text
 
 # assure line feeds don't interfere with our working copy hash
-tests/fixtures/**/*.sh text crlf=input	eol=lf
+**/tests/fixtures/**/*.sh text crlf=input	eol=lf
 /justfile text crlf=input	eol=lf
 
 # have GitHub include fixture-making scripts when it counts code
-tests/fixtures/**/*.sh linguist-vendored=false
+**/tests/fixtures/**/*.sh linguist-vendored=false
 
 # have GitHub treat the gix-packetline-blocking src copy as auto-generated
 gix-packetline-blocking/src/ linguist-generated=true