* fix: 404 for robots.txt and meta robots tags
* fix: add unit tests for robots txt and tag
* fix: add meta tag robots none for login pages
* fix: weird format issue in header.go
* fix: add x-robots-tag=none to grpcwebserver
* fix linting
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Co-authored-by: Silvan <silvan.reusser@gmail.com>
Co-authored-by: Livio Spring <livio.a@gmail.com>