add Scala 3.0.0-M3

[sullis]

https://dotty.epfl.ch/blog/2020/12/18/scala3-m3.html

This PR adds Scala 3.0.0-M3 and drops Scala 3.0.0-M1

[rossabaker]

If this hits problems in CI, I wouldn't mind dropping 3.0.0-M1. The rough guideline on a lot of projects has been to try to support the previous two.

Would be nice to get #64 cleaned up and do another milestone, but I'd prioritize this over that if we're all busy.

[rossabaker]

Looks like there's no scalacheck for all three Dotty milestones. I think that's justification for dropping -M1.

[sullis]

Looks like there's no scalacheck for all three Dotty milestones. I think that's justification for dropping -M1.

I just removed 3.0.0-M1

[sullis]

 sbt ++3.0.0-M3 compile  

Compile error:

[info] compiling 7 Scala sources to /Users/foobar/code/log4s/core/jvm/target/scala-3.0.0-M3/classes ...
[error] -- [E008] Not Found Error: /Users/foobar/code/log4s/core/shared/src/main/scala-3.0.0-M3/org/log4s/LoggerMacros.scala:35:29 
[error] 35 |          if (flags.is(Flags.ModuleClass & Flags.Object)) {
[error]    |                       ^^^^^^^^^^^^^^^^^
[error]    |           value ModuleClass is not a member of qctx.reflect.FlagsModule
[error] one error found
[error] one error found
[error] (coreJVM / Compile / compileIncremental) Compilation failed

Flags.ModuleClass was removed on December 3, 2020

Commit: https://github.com/lampepfl/dotty/commit/5e6fa7245b0689a402e3eb4e2521fd8c707e7aba#diff-798b5c4e3f8e2a24d2eb4b870bf6b5fa348b3f3aa97d1c43471efd0e5e6e1d61

[rossabaker]

The usage of it in that diff changed to Flags.Module. Do the tests still pass if you make the corresponding change here?

[sullis]

The usage of it in that diff changed to Flags.Module. Do the tests still pass if you make the corresponding change here?

I just fixed the compile error. Here's what I changed: https://github.com/Log4s/log4s/pull/67/commits/6c214c2ace9bb3b3ede3ac3737033535bf28465c

[sullis]

the CI build passed 👍