External apps fixes

[diocas]

#6870 brought a couple of issues.. One, is that external apps extension is completely broken, because makeRequest was moved to a different place and never imported into defaultApps.
The second is that the behavior of the method has also changed. (Draw.io is still broken when importing visio files).

The other - not as important - regression is that the app name no longer appears in the title.

[update-docs]

Thanks for opening this pull request! The maintainers of this repository would appreciate it if you would create a changelog item based on your changes.

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

100.0% Coverage
0.0% Duplication

[kulmann]

Hey, thank you for this fix! That's actually blocking the ocis beta.4 release because, as you mentioned, wopi server usage in web is completely broken.
I took the liberty of taking over your PR in #7173 because I was not completely happy with the code duplication for the app name in the document title. I added an option to override the app name in the composable and use it in the App.vue of the external app, instead of your usage in the mounted hook. Hope this is ok.