minor #22885 [3.4] Allow 4.* deps (nicolas-grekas)

This PR was merged into the 3.4 branch.

Discussion
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[3.4] Allow 4.* deps

| Q             | A
| ------------- | ---
| Branch?       | 3.4
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #22756
| License       | MIT
| Doc PR        | -

This is implementing option 3 as described in #22756.
See #22769 for corresponding PR on 2.8: everything goes well and this allows catching a few more potential mistakes.

Commits
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c3e1646af8 [3.4] Allow 4.* deps

Author: fabpot

composer.json

@@ -28,7 +28,7 @@
         "symfony/polyfill-intl-icu": "~1.0"
     },
     "require-dev": {
-        "symfony/filesystem": "~2.8|~3.0|~4.0.0"
+        "symfony/filesystem": "~2.8|~3.0|~4.0"
     },
     "suggest": {
         "ext-intl": "to use the component with locales other than \"en\""