* Add authlib gRPC authenticators for in-proc mode
* implement `StaticRequester` signing in the unified resource client
- [x] when the `claims.AuthInfo` value type is `identity.StaticRequester`, and there's no ID token set, create an internal token and sign it with symmetrical key. This is a workaround for `go-jose` not offering the possibility to create an unsigned token.
- [x] update `IDClaimsWrapper` to support the scenario above
- [x] Switch to using `claims.From()` in `dashboardSqlAccess.SaveDashboard()`
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Co-authored-by: gamab <gabriel.mabille@grafana.com>