feat(plex-login): use application name for plex product name on login

[jordanjones98]

Description

Update the Plex OAuth flow to include the application name. This allows for a tad more customization and authenticating users not being concerned about what "Overseerr" is. The plex product name shows on the plex login screen as shown in the screenshots below.

If the application name is the default Overseerr the plex product name will be Overseerr

If the application name is not the default it will be ${applicationName} - Overseerr.

Screenshot (if UI-related)

Default name of Overseerr

Application name of My Server

To-Dos

• Successful build yarn build
• Translation keys yarn i18n:extract
• Database migration (if required)

[OwsleyJr]

The application title should probably just completely replace the default title of "Overseerr", without the dash. This is how we do it throughout the rest of the app.

[onedr0p]

One of many ways to fix this up @OwsleyJr , if all looks good you should be able to accept my suggests and merge.

[stale]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[lnhrdt]

Consider this not stale! It's a good PR awaiting code owner review from @OwsleyJr, @TheCatLady, @danshilm, and/or @sct.