[PlSql] Fix alphabetic match portability

sql/plsql/PlSqlLexer.g4

@@ -2512,7 +2512,7 @@ SPACES: [ \t\r\n]+ -> channel(HIDDEN);
 
 fragment NEWLINE_EOF    : NEWLINE | EOF;
 fragment QUESTION_MARK  : '?';
-fragment SIMPLE_LETTER  : [\p{Alphabetic}\p{General_Category=Other_Letter}];
+fragment SIMPLE_LETTER  : [A-Z\p{Alphabetic}];
 fragment FLOAT_FRAGMENT : UNSIGNED_INTEGER* '.'? UNSIGNED_INTEGER+;
 fragment NEWLINE        : '\r'? '\n';
 fragment SPACE          : [ \t];

sql/plsql/examples/lexer02.sql

@@ -1,3 +1,7 @@
 select 'A' | | 'B'  from dual;
 
-select a ä, b Ḅ from dual;
+select a ä, b Ḅ from dual;
+
+CREATE OR REPLACE PACKAGE ACCESS_SECURITY AS
+-- omitted
+END;

sql/plsql/examples/lexer02.sql.tree

@@ -0,0 +1 @@
+(sql_script (unit_statement (data_manipulation_language_statements (select_statement (select_only_statement (subquery (subquery_basic_elements (query_block select (selected_list (select_list_elements (expression (logical_expression (unary_logical_expression (multiset_expression (relational_expression (compound_expression (concatenation (concatenation (model_expression (unary_expression (atom (constant (quoted_string 'A')))))) | | (concatenation (model_expression (unary_expression (atom (constant (quoted_string 'B'))))))))))))))) (from_clause from (table_ref_list (table_ref (table_ref_aux (table_ref_aux_internal (dml_table_expression_clause (tableview_name (identifier (id_expression (regular_id dual))))))))))))))))) ; (unit_statement (data_manipulation_language_statements (select_statement (select_only_statement (subquery (subquery_basic_elements (query_block select (selected_list (select_list_elements (expression (logical_expression (unary_logical_expression (multiset_expression (relational_expression (compound_expression (concatenation (model_expression (unary_expression (atom (general_element (general_element_part (id_expression (regular_id a)))))))))))))) (column_alias (identifier (id_expression (regular_id ä))))) , (select_list_elements (expression (logical_expression (unary_logical_expression (multiset_expression (relational_expression (compound_expression (concatenation (model_expression (unary_expression (atom (general_element (general_element_part (id_expression (regular_id b)))))))))))))) (column_alias (identifier (id_expression (regular_id Ḅ)))))) (from_clause from (table_ref_list (table_ref (table_ref_aux (table_ref_aux_internal (dml_table_expression_clause (tableview_name (identifier (id_expression (regular_id dual))))))))))))))))) ; (unit_statement (create_package CREATE OR REPLACE PACKAGE (package_name (identifier (id_expression (regular_id ACCESS_SECURITY)))) AS END)) ; <EOF>)