fontconfig: add static library

[jeroen]

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See: https://docs.brew.sh/Acceptable-Formulae#shared-vs-static-libraries

No need to bump a revision, as we only add an extra file to the bottle. Nothing will be changed or removed.

[github-actions]

🤖 An automated task has requested bottles to be published to this PR.

Caution

Please do not push to this PR branch before the bottle commits have been pushed, as this results in a state that is difficult to recover from. If you need to resolve a merge conflict, please use a merge commit. Do not force-push to this PR branch.

[jeroen]

Thank you!