Fix linter issues in agent-run packages

Replace the single-case switch in the agent-run handler with an if,
and add the blank lines wsl_v5 requires around statements in the
approval checkpoint, worker tests, and policy-set registration.

Signed-off-by: Bryan Frimin <bryan@probo.com>

pkg/probod/probod.go

@@ -595,6 +595,7 @@ func (impl *Implm) Run(
 	)
 
 	agentRunService := agentrun.NewService(pgClient)
+
 	iamService.Authorizer.RegisterPolicySet(agentrun.PolicySet())
 
 	thirdPartyService := thirdparty.NewService(pgClient, fileService, thirdPartyVetter)