Update installation to account for different archive directories between releases and snapshots

[mattnelson]

The changes in #8 were incomplete, they did not account for different archive directories between snapshots and releases.

Releases are archived into apache-maven-$version
Snapshot are archived into apache-maven

Refactored install steps to align with maven's self testing installation process to strip the first directory, which allows this plugin to extract/install releases and snapshots the same way.

https://github.com/apache/maven/blob/master/.github/workflows/maven_build_itself.yml#L59

[flaviogf]

I had the same issue with a specific version. Using this code, I could solve the problem.

[jfharden]

I couldn't install any version of maven anymore (the maven plugin is only listing snapshots):

$ asdf list all maven
3.7.0-SNAPSHOT
3.8.9-SNAPSHOT
3.9.9-SNAPSHOT
4.0.0-alpha-1-SNAPSHOT
4.0.0-alpha-11-SNAPSHOT
4.0.0-alpha-14-SNAPSHOT
4.0.0-alpha-6-SNAPSHOT
4.0.0-beta-1-SNAPSHOT
4.0.0-beta-2-SNAPSHOT
4.0.0-beta-4-SNAPSHOT

Installing any of them leads to the error during install:

mv: rename apache-maven-4.0.0-beta-4-SNAPSHOT/* to ./*: No such file or directory
rmdir: apache-maven-4.0.0-beta-4-SNAPSHOT: No such file or directory

Which leaves me with no working maven install.

I cloned https://github.com/mattnelson/asdf-maven.git into ~/.asdf/plugins/maven and checked out this branch, and now I'm successfully able to install maven again.