brp-mangle-shebangs: also mangle shebangs of JavaScript executables

Fixes https://bugzilla.redhat.com/show_bug.cgi?id=2030427

Unfortunately, the MIME type of JavaScript executables is not text/... but
application/javascript. See RFC 4329.

After considering various approaches to fix this problem, including:

 1) limiting the number of characters `file` reads
 2) using `eu-elfclassify` instead of `file`

This seems like the most sensible approach to fix this one particular problem.
If more instances are found problematic in the future, we'll keep adding the
MIME types.

See the linked bugzilla, the eu-elfclassify pull request [1],
and the devel mailing list thread [2] for details about this problem and
the considered solutions.

[1]: https://src.fedoraproject.org/rpms/redhat-rpm-config/pull-request/145
[2]: https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org/thread/K3QCBUXYR6ZA34I777X6F2RYJKKECJLM/

brp-mangle-shebangs

@@ -76,7 +76,7 @@ cd "$RPM_BUILD_ROOT"
 # (Take care to exclude filenames which would mangle "file" output).
 find -executable -type f ! -path '*:*' ! -path $'*\n*' \
 | file -N --mime-type -f - \
-| grep -P ".+(?=: text/)" \
+| grep -P ".+(?=: (text/|application/javascript))" \
 | {
 fail=0
 while IFS= read -r line; do

redhat-rpm-config.spec

@@ -6,7 +6,7 @@
 
 Summary: Red Hat specific rpm configuration files
 Name: redhat-rpm-config
-Version: 190
+Version: 191
 Release: 1%{?dist}
 # No version specified.
 License: GPL+
@@ -189,6 +189,10 @@ install -p -m 644 -t %{buildroot}%{_rpmluadir}/fedora/srpm forge.lua
 %doc buildflags.md
 
 %changelog
+* Wed Dec 08 2021 Miro Hrončok <mhroncok@redhat.com> - 191-1
+- brp-mangle-shebangs: also mangle shebangs of JavaScript executables
+- Resolves: rhbz#2030427
+
 * Thu Dec 02 2021 Neal Gompa <ngompa@centosproject.org> - 190-1
 - Make vpath builddir not include arch-specific info
   Resolves: rhbz#1984679