Update parser early return type in ESNEXT (#3742)

This patch updates the early return types in the parser to SyntaxError instead of ReferenceError
in ESNEXT

This patch also includes a lot of tests for LeftHandSideExpression validation when using the = operator

JerryScript-DCO-1.0-Signed-off-by: Adam Szilagyi aszilagy@inf.u-szeged.hu

tests/jerry/es.next/array-pattern.js

@@ -309,5 +309,5 @@ try {
   eval ("var a = 0; 1 + [a] = [1]");
   assert (false);
 } catch (e) {
-  assert (e instanceof ReferenceError);
+  assert (e instanceof SyntaxError);
 }