Fix brin "char" test to actually test what it meant to test.

Casting to char, without quotes, does not give the same results as casting
to "char".  That meant we were not testing the brin "char" paths at all,
since we ended up with a text operator not a "char" operator.

src/test/regress/expected/brin.out

@@ -96,7 +96,7 @@ CREATE TABLE brinopers (colname name, typ text, op text[], value text[],
 	check (cardinality(op) = cardinality(value)));
 INSERT INTO brinopers VALUES
 	('byteacol', 'bytea', '{>, >=, =, <=, <}', '{AAAAAA, AAAAAA, BNAAAABNAAAABNAAAABNAAAABNAAAABNAAAABNAAAABNAAAA, ZZZZZZ, ZZZZZZ}'),
-	('charcol', 'char', '{>, >=, =, <=, <}', '{A, A, M, Z, Z}'),
+	('charcol', '"char"', '{>, >=, =, <=, <}', '{A, A, M, Z, Z}'),
 	('namecol', 'name', '{>, >=, =, <=, <}', '{AAAAAA, AAAAAA, MAAAAA, ZZAAAA, ZZAAAA}'),
 	('int2col', 'int2', '{>, >=, =, <=, <}', '{0, 0, 800, 999, 999}'),
 	('int2col', 'int4', '{>, >=, =, <=, <}', '{0, 0, 800, 999, 1999}'),

src/test/regress/sql/brin.sql

@@ -101,7 +101,7 @@ CREATE TABLE brinopers (colname name, typ text, op text[], value text[],
 
 INSERT INTO brinopers VALUES
 	('byteacol', 'bytea', '{>, >=, =, <=, <}', '{AAAAAA, AAAAAA, BNAAAABNAAAABNAAAABNAAAABNAAAABNAAAABNAAAABNAAAA, ZZZZZZ, ZZZZZZ}'),
-	('charcol', 'char', '{>, >=, =, <=, <}', '{A, A, M, Z, Z}'),
+	('charcol', '"char"', '{>, >=, =, <=, <}', '{A, A, M, Z, Z}'),
 	('namecol', 'name', '{>, >=, =, <=, <}', '{AAAAAA, AAAAAA, MAAAAA, ZZAAAA, ZZAAAA}'),
 	('int2col', 'int2', '{>, >=, =, <=, <}', '{0, 0, 800, 999, 999}'),
 	('int2col', 'int4', '{>, >=, =, <=, <}', '{0, 0, 800, 999, 1999}'),