Allow racket-smart-open-bracket-mode in racket-hash-lang-mode; fixes … #1059

Job	Run time
Windows Emacs 29.1 and Racket stable	7m 7s
Ubuntu Emacs 25.1 and Racket 6.12	3m 35s
Ubuntu Emacs 25.1 and Racket stable	3m 47s
Ubuntu Emacs 26.3 and Racket 6.12	2m 25s
Ubuntu Emacs 26.3 and Racket stable	3m 45s
Ubuntu Emacs 29.1 and Racket 6.12	2m 23s
Ubuntu Emacs 29.1 and Racket stable	3m 41s
Ubuntu Emacs snapshot and Racket current	4m 45s
	31m 28s

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