[ExpressionLanguage] replaced the =~ operator by matches (removed the != operator)
minor #9201 [ExpressionLanguage] replaced the =~ operator by matches (removed the != operator) (fabpot)

This PR was merged into the master branch.

Discussion
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[ExpressionLanguage] replaced the =~ operator by matches (removed the != operator)

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | n/a
| License       | MIT
| Doc PR        | n/a

To be consistent with fabpot/Twig#1209

Commits
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4c2d2e2 [ExpressionLanguage] replaced the =~ operator by matches (removed the != operator)