Fix: My account -> My accounts

[Gootector]

Fix: My account -> My accounts
In MuseScore 4.1, there are two accounts:

1. MuseScore.com
2. Audio.com
   so, it should be in the plural.

Greetings,
Gootector

Resolves: #NNNNN

• I signed the CLA
• The title of the PR describes the problem it addresses
• Each commit's message describes its purpose and effects, and references the issue it resolves
• If changes are extensive, there is a sequence of easily reviewable commits
• The code in the PR follows the coding rules
• There are no unnecessary changes
• The code compiles and runs on my machine, preferably after each commit individually
• I created a unit test or vtest to verify the changes I made (if applicable)

[bkunda]

I'm happy with this. Thank you @Gootector!
@cbjeukendrup FYI