PG-603: Fix/Update String::Util module in TAP test perl. (#373)

Removed use of String::Util perl module from TAP test cases, and now using
Text::Trim module instead, as that is more stable. Also removed the
Data::Str2Num perl module as it was not needed any more.

.github/workflows/postgresql-15-pgdg-package.yml

@@ -23,8 +23,7 @@ jobs:
             /etc/postgresql
           sudo rm -f /usr/bin/pg_config
           sudo /usr/bin/perl -MCPAN -e 'install IPC::RUN'
-          sudo /usr/bin/perl -MCPAN -e 'install String::Util'
-          sudo /usr/bin/perl -MCPAN -e 'install Data::Str2Num'
+          sudo /usr/bin/perl -MCPAN -e 'install Text::Trim'
 
       - name: Install PG Distribution Postgresql 15
         run: |