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/agentrun/handler.go

@@ -177,8 +177,7 @@ func (h *handler) executeRun(ctx context.Context, run *coredata.AgentRun) error
 	run.Result = nil
 	run.ErrorMessage = nil
 
-	switch {
-	case runErr == nil:
+	if runErr == nil {
 		run.Status = coredata.AgentRunStatusCompleted
 
 		if result != nil {