Fix sub-command log level (#25537)

More fix for #24981

* #24981


Close #22361

* #22361

There were many patches for Gitea's sub-commands to satisfy the facts:

* Some sub-commands shouldn't output any log, otherwise the git protocol
would be broken
* Sometimes the users want to see "verbose" or "quiet" outputs

That's a longstanding problem, and very fragile. This PR is only a quick
patch for the problem.

In the future, the sub-command system should be refactored to a clear
solution.

----

Other changes:

* Use `ReplaceAllWriters` to replace
`RemoveAllWriters().AddWriters(writer)`, then it's an atomic operation.
* Remove unnecessary `syncLevelInternal` calls, because
`AddWriters/addWritersInternal` already calls it.

Co-authored-by: Giteabot <teabot@gitea.io>

cmd/hook.go

@@ -15,6 +15,7 @@ import (
 	"time"
 
 	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/private"
 	repo_module "code.gitea.io/gitea/modules/repository"
 	"code.gitea.io/gitea/modules/setting"
@@ -32,6 +33,7 @@ var (
 		Name:        "hook",
 		Usage:       "Delegate commands to corresponding Git hooks",
 		Description: "This should only be called by Git",
+		Before:      PrepareConsoleLoggerLevel(log.FATAL),
 		Subcommands: []cli.Command{
 			subcmdHookPreReceive,
 			subcmdHookUpdate,