Fix unescaped character literals

[jeffkowalski]

• Fix a warning that occurs in emacs 27.0+ (unescaped string literals)
• Remove minor extraneous whitespace to satisfy flycheck

[coveralls]

Pull Request Test Coverage Report for Build 273

• 2 of 2 (100.0%) changed or added relevant lines in 1 file are covered.
• 62 unchanged lines in 1 file lost coverage.
• Overall coverage remained the same at 68.491%

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Files with Coverage Reduction	New Missed Lines	%
cmake-ide.el	62	68.49%
<!--	Total:	62		-->

Totals
Change from base Build 272:	0.0%
Covered Lines:	363
Relevant Lines:	530

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💛 - Coveralls

[atilaneves]

Please write tests for this.

[jeffkowalski]

@atilaneves, Coveralls declares my change is already tested, and indeed it's covered by

(ert-deftest test-unquote ()
  (should (equal (cide--unquote "\"foo\"") "foo")))

in test\utils-test.el.

What more would you need?