[REQ] [scala-akka-http-server] Improve handling of pekko versions

[bjolletz]

Is your feature request related to a problem? Please describe.

In the scala-akka-http-server generator, there's an option for using pekko packages instead of akka (useApachePekko). Using this option however, versions of the pekko packages (pekko-stream, pekko-http) are hard-coded to version 1.0.0 without any possibility for a user to alter these versions. These versions are actually not even compatible since pekko-http seems to require pekko-stream >= 1.0.1 to even work.

Describe the solution you'd like

I suggest that pekko versions are handled in the same way as akka versions. This means that:

• The version of pekko-stream is hard-coded (just like akka-stream). The current version is 1.0.3 and I suggest this version is used.
• The version of pekko-http is managed by a paramater (just like akka-http). This means that a new parameter would be added for the scala-akka-http-server generator: pekkoHttpVersion

Describe alternatives you've considered

An alternative would be to keep hard-coding the default pekko versions, but increasing these versions to versions that actually work. Most probably the latest versions.

Additional context

None

[bjolletz]

Solved in #20277