[Filesystem] restore ability to create broken symlinks
bug #13109 [Filesystem] restore ability to create broken symlinks (nicolas-grekas)

This PR was merged into the 2.6 branch.

Discussion
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[Filesystem] restore ability to create broken symlinks

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #12793
| License       | MIT
| Doc PR        | -

Commits
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3101202 [Filesystem] restore ability to create broken symlinks