Fix Forward Deployment Worker causes deadlock

What does this MR do?

This MR fixes that ForwardDeploymentWorker sometimes causes a deadlock. When a job status is updated, the associated deployment's status will also be updated. The order of UPDATE must be executed in the right order, such as UPDATE ci_builds => UPDATE deployments, in order to avoid deadlock. However, currently it looks like the following:

When a build is failed:

[51] pry(main)> b.drop!
   (0.3ms)  BEGIN
  Deployment Update (0.5ms)  UPDATE "deployments" SET "updated_at" = '2020-12-15 18:41:15.967273', "status" = 3, 
         "finished_at" = '2020-12-15 18:41:15.964140' WHERE "deployments"."id" = 34
  Ci::Build Update (0.5ms)  UPDATE "ci_builds" SET "status" = 'failed', "finished_at" = '2020-12-15 18:41:15.960797', 
         "updated_at" = '2020-12-15 18:41:15.970301', "processed" = FALSE, "lock_version" = 4 WHERE "ci_builds"."id" = 14 
         AND "ci_builds"."lock_version" = 3
   (0.7ms)  COMMIT

while when the build is skipped/canceled, it instead does:

[63] pry(main)> b.skip
   (0.2ms)  BEGIN
  Ci::Build Update (0.7ms)  UPDATE "ci_builds" SET "status" = 'skipped', "updated_at" = '2020-12-15 19:12:03.676005', 
          "processed" = FALSE, "lock_version" = 8 WHERE "ci_builds"."id" = 14 AND "ci_builds"."lock_version" = 7
  Deployment Update (0.4ms)  UPDATE "deployments" SET "updated_at" = '2020-12-15 19:12:03.680070', "status" = 4, 
          "finished_at" = '2020-12-15 19:12:03.679611' WHERE "deployments"."id" = 34
   (0.7ms)  COMMIT

To illustrate the problem:

job A fails -> lock CI record -> lock deployment record -> commit
                       |--deadlock--|
     commit <- lock CI record <- lock deployment record <- job B gets skipped <- Job A fails

This MR fixes the wrong hook in Ci::Build to execute the UPDATE deployments after the Update builds.

Huge thanks to @pbair for the initial investigation on the issue.

Related #297496 (closed) #297496 (closed)

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