Fix textproto filetypes

[TylerJang27]

Brought to attention by https://github.com/trunk-io/plugins/issues/832. Brought up to date to support the filetypes defined here

[trunk-io[bot]]

⏱️ 42m total CI duration on this PR

Job	Cumulative Duration	Recent Runs
Linter Tests ubuntu-latest	22m	🟩
Linter Tests macOS	15m	🟩
Trunk Check runner [linux]	3m	🟩
CodeQL-Build	1m	🟩
Repo Tests / Plugin Tests	31s	🟩
Detect changed files	4s	🟩
Aggregate Test Results	1s	🟩

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