Replacing {require,assert}.{Nil,NotNil} with {require,assert}.{NoError,Error} in the store tests (when comparing errors) (#16886)

* Replacing require.Nil with require.NoError

* More replacements

* More Nil/NotNill to NoError/Error

* Other detected errors

* renaming apperr to err

* Removed not needed line

* Rename old appErr variables that are no longer model.AppError values

* Fixing tiny typo

* Reverting changes outside the store (accidentally added)

* Apply suggestions from code review

Co-authored-by: Doug Lauder <wiggin77@warpmail.net>

Co-authored-by: Doug Lauder <wiggin77@warpmail.net>

store/sqlstore/session_store.go

@@ -249,9 +249,9 @@ func (me SqlSessionStore) UpdateDeviceId(id string, deviceId string, expiresAt i
 }
 
 func (me SqlSessionStore) UpdateProps(session *model.Session) error {
-	oldSession, appErr := me.Get(session.Id)
-	if appErr != nil {
-		return appErr
+	oldSession, err := me.Get(session.Id)
+	if err != nil {
+		return err
 	}
 	oldSession.Props = session.Props