pgsql: Add a script to detect perl compile time errors and warnings

Add a script to detect perl compile time errors and warnings

Also add a function that centralizes the logic for locating all our perl
files and use it in pgperlcritic and pgperltidy as well as the new
pgperlcheck.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/af616ce48347c68af7bdcfe0e62d9ad601cb8d75

Modified Files
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src/tools/perlcheck/find_perl_files | 15 +++++++++++++++
src/tools/perlcheck/pgperlsyncheck | 16 ++++++++++++++++
src/tools/pgindent/pgperltidy | 14 +++-----------
src/tools/pgperlcritic/pgperlcritic | 14 +++-----------
4 files changed, 37 insertions(+), 22 deletions(-)