* ngalert openapi: Use same `basePath` as rest of Grafana
Currently, there are two issues that prevent easily merging `ngalert` and grafana openapi specs:
- The basePath is different. `grafana` has `/api` and `ngalert` has `/api/v1`. I changed `ngalert` to use `/api`
- The `ngalert` endpoints have their basePath in the each operation path. The basePath should actually be omitted
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Co-authored-by: Yuriy Tseretyan <yuriy.tseretyan@grafana.com>