Revert "[MM-41576] Revamp database schema version (#19586)" (#19746)

* Revert "[MM-41576] Revamp database schema version (#19586)"

This reverts commit 645fee3fe3.

* Revert "MM-42049 - license endpoint not working (#19686)"

This reverts commit 4fe89e5847.

app/post_test.go

@@ -464,7 +464,6 @@ func TestImageProxy(t *testing.T) {
 	mockStore.On("User").Return(&mockUserStore)
 	mockStore.On("Post").Return(&mockPostStore)
 	mockStore.On("System").Return(&mockSystemStore)
-	mockStore.On("GetDBSchemaVersion").Return(1, nil)
 
 	th.App.UpdateConfig(func(cfg *model.Config) {
 		*cfg.ServiceSettings.SiteURL = "http://mymattermost.com"