Meta: add yet phrase checking using ESMeta

[jhnaldo]

This PR supports the checking of newly introduced phrases using ESMeta related to the following issue:

• mode to warn about newly-introduced novel phrasing es-meta/esmeta#289

The main feature is developed in the following PR:

• Support CI Warning for Newly Introduced Phrases es-meta/esmeta#302

You can see the test results of this check as follows:

PR	Author	Name	Added/Modified Lines	Unknown Step	Unknown Type
#3655	Kevin Gibbons	test1	406	6	4
#3660	mobius29	test2	1	0	0
#3691	Kevin Gibbons	test3	1	0	0
#3513	Richard Gibson	test4	14	2	1
#3595	Aapo Alasuutari	test5	3	0	0
#3608	Michael Ficarra	test6	1	0	0
#3613	Nicolò Ribaudo	test7	2	0	0
#3613	Jordan Harband	test8	1	0	0
#3619	Richard Gibson	test9	7	0	0
#3620	André Bargull	test10	326	0	0
#3664	mobius29	test11	2	0	0
#3687	Nicolò Ribaudo	test12	5	0	0
#3694	YAMAMOTO Yuji	test13	1	0	0

[michaelficarra]

LGTM otherwise.

[bakkot]

LGTM other than switching to a sha rather than a mutable tag.

[jhnaldo]

I updated this PR to use SHA rather than a mutable tag.