feat: Remove syncNotion from ConnectionCards (#3289)

The syncNotion function is no longer needed in the ConnectionCards
component, so it has been removed. This change simplifies the code and
improves maintainability.

# Description

Please include a summary of the changes and the related issue. Please
also include relevant motivation and context.

## Checklist before requesting a review

Please delete options that are not relevant.

- [ ] My code follows the style guidelines of this project
- [ ] I have performed a self-review of my code
- [ ] I have commented hard-to-understand areas
- [ ] I have ideally added tests that prove my fix is effective or that
my feature works
- [ ] New and existing unit tests pass locally with my changes
- [ ] Any dependent changes have been merged

## Screenshots (if appropriate):

frontend/lib/components/ConnectionCards/ConnectionCards.tsx

@@ -10,7 +10,7 @@ interface ConnectionCardsProps {
 export const ConnectionCards = ({
   fromAddKnowledge,
 }: ConnectionCardsProps): JSX.Element => {
-  const { syncGoogleDrive, syncSharepoint, syncDropbox, syncNotion } =
+  const { syncGoogleDrive, syncSharepoint, syncDropbox } =
     useSync();
 
   return (
@@ -30,13 +30,13 @@ export const ConnectionCards = ({
         callback={(name: string) => syncGoogleDrive(name)}
         fromAddKnowledge={fromAddKnowledge}
       />
-      <ConnectionSection
+      {/* <ConnectionSection
         label="Notion (Beta)"
         provider="Notion"
         callback={(name: string) => syncNotion(name)}
         fromAddKnowledge={fromAddKnowledge}
         oneAccountLimitation={true}
-      />
+      /> */}
       <ConnectionSection
         label="Sharepoint"
         provider="Azure"