fix error with unique album constraint

[Mnigos]

• implement findOrCreate method with ids in tracksService
  needed in:

findOrCreateAlbumFromExternalId

 if (foundAlbum?.tracks && foundAlbum.tracks.length > 0) {
    const tracks = await this.tracksService.create(
                                            ^^^^^^ => `findOrCreate`
      albumToCreate.tracks.items.map(track => track.id),
      [foundAlbum]
    )
    
    foundAlbum.tracks = tracks
    
    return this.albumsRepository.save(foundAlbum)
  }

findOrCreateAlbumFromExternalId

    for (const foundAlbum of foundAlbums) {
      const albumToCreate = fetchedAlbums.find(
        ({ id }) => id === foundAlbum.externalId
      )

      if (foundAlbum.tracks && foundAlbum.tracks.length > 0 && albumToCreate) {
        await this.tracksService.create(
                                 ^^^^^^ => `findOrCreate`
          albumToCreate.tracks.items.map(track => track.id),
          [foundAlbum]
        )
      }
    }

• save album with new tracks

      if (foundAlbum.tracks && foundAlbum.tracks.length > 0 && albumToCreate) {
        await this.tracksService.create(
          albumToCreate.tracks.items.map(track => track.id),
          [foundAlbum]
        )
      }

• filter albums before creating tracks
  by externalId and tracks length

[codecov]

Codecov Report

Attention: Patch coverage is 47.61905% with 33 lines in your changes are missing coverage. Please review.

Project coverage is 85.61%. Comparing base (c2c8924) to head (aa24838).

❗ Current head aa24838 differs from pull request most recent head 57d6c41. Consider uploading reports for the commit 57d6c41 to get more accurate results

Files	Patch %	Lines
src/modules/tracks/tracks.service.ts	23.25%	33 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #216      +/-   ##
==========================================
- Coverage   86.46%   85.61%   -0.85%     
==========================================
  Files          53       53              
  Lines        3014     3066      +52     
  Branches      388      392       +4     
==========================================
+ Hits         2606     2625      +19     
- Misses        408      441      +33     

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