fixed grammar mistakes

src/server/routes/apiv3/slack-integration-settings.js

@@ -390,7 +390,7 @@ module.exports = (crowi) => {
       return res.apiv3(slackAppTokens, 200);
     }
     catch (error) {
-      const msg = 'Error occurred while creating slack integration settings procedure';
+      const msg = 'Error occurred during creating slack integration settings procedure';
       logger.error('Error', error);
       return res.apiv3Err(new ErrorV3(msg, 'creating-slack-integration-settings-procedure-failed'), 500);
     }
@@ -420,7 +420,7 @@ module.exports = (crowi) => {
       return res.apiv3(slackAppTokens, 200);
     }
     catch (error) {
-      const msg = 'Error occurred while regenerating slack app tokens';
+      const msg = 'Error occurred during regenerating slack app tokens';
       logger.error('Error', error);
       return res.apiv3Err(new ErrorV3(msg, 'regenerating-slackAppTokens-failed'), 500);
     }