Add debian "testing" release

[sktt]

Hey there, I had an issue with getting this up and running on debian/testing. Here's a debug log snippet

  MongoMS:MongoBinary MongoBinary options: {"downloadDir":"/home/jnes/TILLY/delta/jest/node_modules/.cache/mongodb-memory-server/mongodb-binaries","platform":"linux","arch":"x64","version":"4.0.14"} +0ms
  MongoMS:getos Trying LSB-Release +0ms
  MongoMS:MongoBinaryDownloadUrl Using "mongodb-linux-x86_64-debian-4.0.14.tgz" as the Archive String +0ms
  MongoMS:MongoBinaryDownloadUrl Using "https://fastdl.mongodb.org" as the mirror +0ms
  MongoMS:MongoBinaryDownload Downloading: "https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-debian-4.0.14.tgz" +0ms
  MongoMS:MongoBinaryDownload trying to download https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-debian-4.0.14.tgz +0ms
Error: Status Code is 403 (MongoDB's 404)

The problem here is not only the version number (using latest gives the same error) but also that it seems debian should be suffixed with its version number too.

Since Debian unstable falls back to 10, I think it should be OK for the slightly less bleeding edge Debian testing to do the same.

Related issue

There's none but one can reproduce by installing debian testing, whose lsb_release -a looks like so

No LSB modules are available.
Distributor ID: Debian
Description:    Debian GNU/Linux bullseye/sid
Release:        testing
Codename:       bullseye

[codecov]

Codecov Report

Merging #430 (5d28f68) into master (01a6bc6) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #430   +/-   ##
=======================================
  Coverage   78.08%   78.08%           
=======================================
  Files           9        9           
  Lines         981      981           
  Branches      268      277    +9     
=======================================
  Hits          766      766           
+ Misses        214      213    -1     
- Partials        1        2    +1     

Impacted Files	Coverage Δ
...ory-server-core/src/util/MongoBinaryDownloadUrl.ts	72.77% <100.00%> (ø)
...ongodb-memory-server-core/src/MongoMemoryServer.ts	92.07% <0.00%> (ø)

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[github-actions]

🎉 This PR is included in version 6.9.3 🎉

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[github-actions]

🎉 This PR is included in version 7.0.0-beta.48 🎉

The release is available on:

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• npm package (@beta dist-tag)
• npm package (@beta dist-tag)
• npm package (@beta dist-tag)
• npm package (@beta dist-tag)
• npm package (@beta dist-tag)
• GitHub release

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