pgsql: Teach RPM the package name provided in Perl alias packages.

Teach RPM the package name provided in Perl alias packages.

When commit 1185be355462d1dc7e2950a7e52eb7ca0cb6f3c8 introduced
installation of a file containing "use PostgreSQL::Test::Utils", the RPM
Package Manager said "nothing provides perl(PostgreSQL::Test::Utils)".
Discussed on pgsql-packagers. Back-patch to v12, v13, and v14 only;
newer versions don't have the alias packages.

Reviewed by Andrew Dunstan, Tom Lane, and John Harvey. Reported by John
Harvey.

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/ecf7c48462396b98c50d32cc77ec5a024fefc34c

Modified Files
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src/test/perl/PostgreSQL/Test/Cluster.pm | 6 ++++++
src/test/perl/PostgreSQL/Test/Utils.pm | 6 ++++++
2 files changed, 12 insertions(+)