Make internal query() retryable

When `permanent_connection_checkout` was [introduced][1], Active Record
was changed to always use `with_connection` and [never][2]
`lease_connection`. This causes apps that never call `lease_connection`
on their own (or in a gem) during a request to no longer have a
connection pinned to the current Thread/Fiber. By checking in/out
connections as needed, the number of times a connection must be verified
during a single request has significantly increased (more pings = more
latency).

The good news is that Active Record also now [defers][3] connection
verification and can use retryable queries as verification instead of
explicit pings.

This commit makes all internal SELECT `query()`s retryable so that they
can be used as connection verification. While this likely won't help as
much in production for applications using a schema cache dump, it will
definitely decrease latency for applications in development and those
that do not use a dump in production.

There are a few places where `query_value` was used to update sequences.
Those have been changed to use `internal_execute` since only idempotent
SELECT queries are being automatically retried and Active Record doesn't
actually care about the return value of these queries anyways (so no
reason to use `internal_exec_query`).

[1]: 4db9f51
[2]: 7c68c52
[3]: 7fe221d

Author: skipkayhil

activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb

@@ -110,8 +110,8 @@ def query_values(...) # :nodoc:
         query(...).map(&:first)
       end
 
-      def query(...) # :nodoc:
-        internal_exec_query(...).rows
+      def query(sql, name = nil, allow_retry: true, materialize_transactions: true) # :nodoc:
+        internal_exec_query(sql, name, allow_retry:, materialize_transactions:).rows
       end
 
       # Determines whether the SQL statement is a write query.

activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb

@@ -320,7 +320,7 @@ def set_pk_sequence!(table, value) # :nodoc:
             if sequence
               quoted_sequence = quote_table_name(sequence)
 
-              query_value("SELECT setval(#{quote(quoted_sequence)}, #{value})", "SCHEMA")
+              internal_execute("SELECT setval(#{quote(quoted_sequence)}, #{value})", "SCHEMA")
             else
               @logger.warn "#{table} has primary key #{pk} with no default sequence." if @logger
             end
@@ -351,7 +351,7 @@ def reset_pk_sequence!(table, pk = nil, sequence = nil) # :nodoc:
               end
             end
 
-            query_value("SELECT setval(#{quote(quoted_sequence)}, #{max_pk || minvalue}, #{max_pk ? true : false})", "SCHEMA")
+            internal_execute("SELECT setval(#{quote(quoted_sequence)}, #{max_pk || minvalue}, #{max_pk ? true : false})", "SCHEMA")
           end
         end