bug #27889 [Form] Replace .initialism with .text-uppercase. (vudaltsov)
bug #27889 [Form] Replace .initialism with .text-uppercase. (vudaltsov)

This PR was merged into the 3.4 branch.

Discussion
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[Form] Replace .initialism with .text-uppercase.

| Q             | A
| ------------- | ---
| Branch?       | 3.4
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets |
| License       | MIT
| Doc PR        |

I think that the `.initialism` [class](https://getbootstrap.com/docs/4.0/content/typography/#abbreviations) is for different purposes. While the `.text-uppercase` [class](https://getbootstrap.com/docs/4.0/utilities/text/#text-transform) is more neutral and does exactly what we want here.

Commits
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3c39dfdaa6 Replace .initialism with .text-uppercase.

symfony/TwigBridge,symfony/twig-bridge