Allow only upper case operator names

Allow only upper case predefined selector literals and operator names.

The JMS spec states:
> Predefined selector literals and operator names are written here in upper case; however, they are case insensitive.

However, the AMQP SQL spec does not include such a statement.
The EBNF notation with single quotes ('AND') typically implies exact literal matching.
This commit follows the AMQP SQL's EBNF notation and therefore disallows
lower case predefined selector literals or operator names.

Author: ansd

deps/rabbit/src/rabbit_amqp_sql_ast.erl

@@ -77,7 +77,7 @@ has_binary_identifier_test() ->
     false = has_binary_identifier("properties.group-sequence * 10 < 100"),
     false = has_binary_identifier("properties.creation-time >= 12345 OR properties.subject = 'test'"),
     true = has_binary_identifier("user_key = 'g1' AND header.priority > 5"),
-    true = has_binary_identifier("header.priority > 5 and user_key = 'g1'"),
+    true = has_binary_identifier("header.priority > 5 AND user_key = 'g1'"),
     true = has_binary_identifier("custom_metric * 10 < 100"),
     true = has_binary_identifier("properties.creation-time >= 12345 OR user_data = 'test'"),