MM-13893: refactor config (#10230)

* refactor utils/config* to config/

* pull validateLdapFilter into app

* clean up Config/GetConfig/GetSanitizedConfig usage

Eliminate app.GetConfig() in favour of just using app.Config() directly,
but expose app.GetSanitizedConfig() for when the old behaviour was
required.

* web: isolate config setup

* TestInvitePeopleProvider: make config explicit

* regenerateClientConfig: avoid racey map access

* integrate watch flag into app.ConfigFile option

* make app.Option return an error

* release.mk: only cp static files from config/

* release.mk: fix cp static files from config/

* api4: TestPlugin cleanup

* s/c/cfg/ for clarity

* fix merge conflict

* testlib: allow customization of testlib driver name

api4/user.go

@@ -856,7 +856,7 @@ func updateUserActive(c *Context, w http.ResponseWriter, r *http.Request) {
 	}
 
 	// if EnableUserDeactivation flag is disabled the user cannot deactivate himself.
-	if isSelfDeactive && !*c.App.GetConfig().TeamSettings.EnableUserDeactivation {
+	if isSelfDeactive && !*c.App.Config().TeamSettings.EnableUserDeactivation {
 		c.Err = model.NewAppError("updateUserActive", "api.user.update_active.not_enable.app_error", nil, "userId="+c.Params.UserId, http.StatusUnauthorized)
 		return
 	}