fix: stop including embedded compiler in ktlint tasks

[ianbotsf]

Issue #, if available:

(none)

Description of changes:

Slimmed down version of #70 that focuses strictly on eliminating this compiler warning:

w: The artifact `org.jetbrains.kotlin:kotlin-compiler-embeddable` is present in the build classpath along Kotlin Gradle plugin.
This may lead to unpredictable and inconsistent behavior.
For more details, see: https://kotl.in/gradle/internal-compiler-symbols

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[lauzadis]

Do we also want to take the ktlintVersion deduplication change you made?

[ianbotsf]

Turns out this PR is broken. aws-kotlin-repo-tools builds and passes ktlint just fine but upstream projects fail to run ktlint because of the removed kotlin-compiler-embeddable transitive dependency. Got to spend some more time debugging this.

[ianbotsf]

OK now I think it's right. Ready for second review!

[lauzadis]

Do we really have to downgrade our ktlint version to get this fix? If so, could we open an issue to Ktlint to fix this problem, so we are unblocked for future upgrades?

[ianbotsf]

The downgrade is to match the version we were previously setting explicitly in configureLinting. In that sense, it's only a downgrade for aws-kotlin-repo-tools which was previously using 1.5.0.

The 1.5.0 version actually isn't relevant to the compiler warning. The same warning happened whether we used 1.3.0 or 1.5.0. The actual problem was using the non-shadowed ktlint-cli variant.