Update OIDC claim mapping table to reflect the current state (#1801)

* Update Buildkite column in OIDC claim mapping table

Signed-off-by: Richard Fan <[email protected]>

* Remove CircleCI from OIDC claim mapping table

Signed-off-by: Richard Fan <[email protected]>

* Remove WIP remark from GitLab OIDC claim mapping tabl

Signed-off-by: Richard Fan <[email protected]>

* Update GitLab OIDC claims mapping table

Signed-off-by: Richard Fan <[email protected]>

* Add double quotes on literal string in OIDC claim mapping table

Signed-off-by: Richard Fan <[email protected]>

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Signed-off-by: Richard Fan <[email protected]>