Cache PostgresqlAdapter type map

What does this MR do?

Caches this type map query that gets executed every time we open a PG connection:

SELECT t.oid, t.typname, t.typelem, t.typdelim, t.typinput, r.rngsubtype, t.typtype, t.typbasetype
FROM pg_type as t
LEFT JOIN pg_range as r ON oid = rngtypid
WHERE
  t.typname IN ('int2', 'int4', 'int8', 'oid', 'float4', 'float8', 'text', 'varchar', 'char', 'name', 'bpchar', 'bool', 'bit', 'varbit', 'timestamptz', 'date', 'money', 'bytea', 'point', 'hstore', 'json', 'jsonb', 'cidr', 'inet', 'uuid', 'xml', 'tsvector', 'macaddr', 'citext', 'ltree', 'line', 'lseg', 'box', 'path', 'polygon', 'circle', 'time', 'timestamp', 'numeric', 'interval')
  OR t.typtype IN ('r', 'e', 'd')
  OR t.typinput = 'array_in(cstring,oid,integer)'::regprocedure
  OR t.typelem != 0

Related to #331786 (closed)

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