In #15178, we're switching hard-coded constants in tests to insta.

This issue targets updating sql tests (datafusion/sql).

Examples of tests that need to be switched to insta:

• datafusion/datafusion/sql/tests/sql_integration.rs

  Lines 95 to 99 in 45ed5aa

  	fn parse_ident_normalization() {
  	let test_data = [
  	(
  	"SELECT CHARACTER_LENGTH('str')",
  	"Ok(Projection: character_length(Utf8(\"str\"))\n EmptyRelation)",

• datafusion/datafusion/sql/tests/sql_integration.rs

  Lines 962 to 966 in 45ed5aa

  	let expected = "Projection: person.first_name AS fn, max(person.age)\
  	\n Filter: max(person.age) > Int64(2) AND person.first_name = Utf8(\"M\")\
  	\n Aggregate: groupBy=[[person.first_name]], aggr=[[max(person.age)]]\
  	\n TableScan: person";
  	quick_test(sql, expected);

• datafusion/datafusion/sql/tests/sql_integration.rs

  Lines 1353 to 1356 in 45ed5aa

  	quick_test(
  	"SELECT ((age + 1) / 2) * (age + 1), MIN(first_name) FROM person GROUP BY age + 1",
  	"Projection: person.age + Int64(1) / Int64(2) * person.age + Int64(1), min(person.first_name)\
  	\n Aggregate: groupBy=[[person.age + Int64(1)]], aggr=[[min(person.first_name)]]\

Check the original issue for tips on how to do the switch and examples of completed PRs.