Parser: make an error on unbalanced end brace '}' in macro body (#5420)

Fixed #5417

spec/compiler/parser/parser_spec.cr

@@ -780,6 +780,7 @@ describe "Parser" do
   it_parses "macro foo;bar{% for x in y %}\\  \n   body{% end %}\\   baz;end", Macro.new("foo", [] of Arg, Expressions.from(["bar".macro_literal, MacroFor.new(["x".var], "y".var, "body".macro_literal), "baz;".macro_literal] of ASTNode))
   it_parses "macro foo; 1 + 2 {{foo}}\\ 3 + 4; end", Macro.new("foo", [] of Arg, Expressions.from([" 1 + 2 ".macro_literal, MacroExpression.new("foo".var), "3 + 4; ".macro_literal] of ASTNode))
 
+  assert_syntax_error "macro foo; {% foo = 1 }; end"
   assert_syntax_error "macro def foo : String; 1; end"
 
   it_parses "def foo;{{@type}};end", Def.new("foo", body: Expressions.from([MacroExpression.new("@type".instance_var)] of ASTNode), macro_def: true)

src/compiler/crystal/syntax/parser.cr

@@ -2870,6 +2870,7 @@ module Crystal
         when :MACRO_CONTROL_START
           macro_control = parse_macro_control(start_line, start_column, macro_state)
           if macro_control
+            check :"%}"
             pieces << macro_control
             skip_whitespace = check_macro_skip_whitespace
           else