chore(*): remove unused code (#6781)

The code removed in the PR was flagged as unused by the JetBrains
inspector.

I did a QA on the dev environment but other checks are highly
recommended.

There is one commit by scope to make the review easier.

---------

Co-authored-by: Charles Bochet <charles@twenty.com>

packages/twenty-server/src/engine/core-modules/file/services/file.service.ts

@@ -38,7 +38,7 @@ export class FileService {
 
     const expirationDate = addMilliseconds(new Date(), ms(fileTokenExpiresIn));
 
-    const signedPayload = await this.jwtWrapperService.sign(
+    const signedPayload = this.jwtWrapperService.sign(
       {
         expiration_date: expirationDate,
         ...payloadToEncode,