fix: getProcedures returns only procedures (not functions) for psql11+

[MSGoodman]

Currently the PGDatabaseMetaData.getProcedures() method returns both
procedures and functions. This made sense prior to PostgreSQL11, but now
actual procedures can be created instead of just functions, and pgjdbc
has an added getFunctions() method to distinguish between the two. For
only PostgreSQL version 11 and onward, this will make getFunctions()
return only functions and getProcedures() return only procedures.

I believe this closes #1340 and closes #1629, which both seem to essentially be
the same thing?

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Changes to Existing Features:

• [?] Does this break existing behaviour? If so please explain.

I am unsure if this should be considered breaking. Since PostgreSQL 11 has been out since 2018, I assume there is some code out there relying on the assumption that getProcedures() returns both functions and procedures rather than just procedures. ¯\(ツ)/¯

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[MSGoodman]

Ah, silly me, I try to do create procedure in the setup regardless of the postgres version, which obviously causes issues, fixing now

[MSGoodman]

Hrm, my apologies, I also need to fix testGetProcedures. It appears I had an owner-superuser so that test wasn't running correctly. Will correct promptly.

[codecov-io]

Codecov Report

Merging #1723 into master will increase coverage by 0.11%.
The diff coverage is 50%.

@@             Coverage Diff              @@
##             master    #1723      +/-   ##
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+ Coverage      69.3%   69.42%   +0.11%     
- Complexity     4195     4201       +6     
============================================
  Files           187      187              
  Lines         17265    17278      +13     
  Branches       2870     2872       +2     
============================================
+ Hits          11966    11995      +29     
+ Misses         4015     3997      -18     
- Partials       1284     1286       +2