Remove ES_NEXT macro (#4915)

- remove all '#JERRY_ESNEXT' macro
- remove 5.1 build profile, update test runner accordingly (Note: all builtins are turn on by default)
- move tests from tests/jerry/esnext into tests/jerry, concatenate files with same names
- add skiplist to some snapshot tests that were supported only in 5.1
- fix doxygen issues that were hidden before (bc. of es.next macro)

Co-authored-by: Martin Negyokru negyokru@inf.u-szeged.hu
JerryScript-DCO-1.0-Signed-off-by: Adam Szilagyi aszilagy@inf.u-szeged.hu

jerry-core/ecma/operations/ecma-promise-object.h

@@ -18,8 +18,6 @@
 
 #include "ecma-globals.h"
 
-#if JERRY_ESNEXT
-
 /** \addtogroup ecma ECMA
  * @{
  *
@@ -46,8 +44,8 @@ typedef enum
  */
 typedef struct
 {
-  ecma_extended_object_t header;
-  ecma_value_t promise;
+  ecma_extended_object_t header; /**< extended object part */
+  ecma_value_t promise; /**< [[Promise]] internal slot */
 } ecma_promise_resolver_t;
 
 /**
@@ -145,5 +143,4 @@ ecma_value_t ecma_promise_perform_then (ecma_value_t promise,
  * @}
  */
 
-#endif /* JERRY_ESNEXT */
 #endif /* !ECMA_PROMISE_OBJECT_H */