Roll a release (2.8.1)

[SethTisue]

to ship the scalafix upgrade (#549)

since there are no changes to the library itself, only to the scalafix aspect, I suggest we call it 2.8.1 rather than to go 2.9.0

after the release, we should merge #550

[SethTisue]

• release: https://github.com/scala/scala-collection-compat/releases/tag/v2.8.1
• publishing job: https://github.com/scala/scala-collection-compat/actions/runs/2757669560

[SethTisue]

sigh

[error] (compat3Native / versionCheck) Module scala-collection-compat has an invalid version number: 2.8.1. You must increment the minor version number to publish a source incompatible release.
[35](https://github.com/scala/scala-collection-compat/runs/7571176952?check_suite_focus=true#step:4:36)
[error] (compat211Native / versionCheck) Module scala-collection-compat has an invalid version number: 2.8.1. You must increment the minor version number to publish a source incompatible release.
[36](https://github.com/scala/scala-collection-compat/runs/7571176952?check_suite_focus=true#step:4:37)
[error] (compat3JS / versionCheck) Module scala-collection-compat has an invalid version number: 2.8.1. You must increment the minor version number to publish a source incompatible release.
[37](https://github.com/scala/scala-collection-compat/runs/7571176952?check_suite_focus=true#step:4:38)
[error] (compat212Native / versionCheck) Module scala-collection-compat has an invalid version number: 2.8.1. You must increment the minor version number to publish a source incompatible release.
[38](https://github.com/scala/scala-collection-compat/runs/7571176952?check_suite_focus=true#step:4:39)
[error] (compat213Native / versionCheck) Module scala-collection-compat has an invalid version number: 2.8.1. You must increment the minor version number to publish a source incompatible release.
[39](https://github.com/scala/scala-collection-compat/runs/7571176952?check_suite_focus=true#step:4:40)
[error] (compat211 / versionCheck) Module scala-collection-compat has an invalid version number: 2.8.1. You must increment the minor version number to publish a source incompatible release.
[40](https://github.com/scala/scala-collection-compat/runs/7571176952?check_suite_focus=true#step:4:41)
[error] (compat211JS / versionCheck) Module scala-collection-compat has an invalid version number: 2.8.1. You must increment the minor version number to publish a source incompatible release.
[41](https://github.com/scala/scala-collection-compat/runs/7571176952?check_suite_focus=true#step:4:42)
[error] (compat212JS / versionCheck) Module scala-collection-compat has an invalid version number: 2.8.1. You must increment the minor version number to publish a source incompatible release.
[42](https://github.com/scala/scala-collection-compat/runs/7571176952?check_suite_focus=true#step:4:43)
[error] (compat213 / versionCheck) Module scala-collection-compat has an invalid version number: 2.8.1. You must increment the minor version number to publish a source incompatible release.
[43](https://github.com/scala/scala-collection-compat/runs/7571176952?check_suite_focus=true#step:4:44)
[error] (compat212 / versionCheck) Module scala-collection-compat has an invalid version number: 2.8.1. You must increment the minor version number to publish a source incompatible release.
[44](https://github.com/scala/scala-collection-compat/runs/7571176952?check_suite_focus=true#step:4:45)
[error] (compat213JS / versionCheck) Module scala-collection-compat has an invalid version number: 2.8.1. You must increment the minor version number to publish a source incompatible release.
[45](https://github.com/scala/scala-collection-compat/runs/7571176952?check_suite_focus=true#step:4:46)
[error] (compat3 / versionCheck) Module scala-collection-compat has an invalid version number: 2.8.1. You must increment the minor version number to publish a source incompatible release.```

[SethTisue]

ah, #553 should take care of it

[SethTisue]

• release: https://github.com/scala/scala-collection-compat/releases/tag/v2.8.1
• publishing job: https://github.com/scala/scala-collection-compat/actions/runs/2757737299