`ratchetFrom` doesn't support merge conflicts

[blacelle]

This is an edge case.

I consider a local repository, during a merge conflict. I end with some files being removed locally, but in conflict with the remote head: during the conflict-management process, I end with something like:

cleanthat git status
On branch IntroduceSpotLess
Your branch is up to date with 'origin/IntroduceSpotLess'.

You have unmerged paths.
  (fix conflicts and run "git commit")
  (use "git merge --abort" to abort the merge)

Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)
	deleted by us:   java/src/test/java/eu/solven/cleanthat/language/java/rules/test/ATestCases.java

Changes not staged for commit:
  (use "git add <file>..." to update what will be committed)
  (use "git restore <file>..." to discard changes in working directory)
	modified:   java/src/test/java/eu/solven/cleanthat/language/java/refactorer/test/ARefactorerCases.java
	modified:   java/src/test/java/eu/solven/cleanthat/language/java/refactorer/test/ATestCases.java

Here, I'm moving java/src/test/java/eu/solven/cleanthat/language/java/rules/test/ATestCases.java into java/src/test/java/eu/solven/cleanthat/language/java/refactorer/test/ARefactorerCases.java

I end with an issue like:

[ERROR] Failed to execute goal com.diffplug.spotless:spotless-maven-plugin:2.30.0:apply (applySpotless) on project java: Unable to format file /Users/blacelle/workspace3/cleanthat/java/src/test/java/eu/solven/cleanthat/language/java/rules/test/ATestCases.java -> [Help 1]
org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal com.diffplug.spotless:spotless-maven-plugin:2.30.0:apply (applySpotless) on project java: Unable to format file /Users/blacelle/workspace3/cleanthat/java/src/test/java/eu/solven/cleanthat/language/java/rules/test/ATestCases.java
...
Caused by: org.apache.maven.plugin.MojoExecutionException: Unable to format file /Users/blacelle/workspace3/cleanthat/java/src/test/java/eu/solven/cleanthat/language/java/rules/test/ATestCases.java
    at com.diffplug.spotless.maven.SpotlessApplyMojo.process (SpotlessApplyMojo.java:51)
    at com.diffplug.spotless.maven.AbstractSpotlessMojo.execute (AbstractSpotlessMojo.java:214)
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo (DefaultBuildPluginManager.java:137)
...
Caused by: java.nio.file.NoSuchFileException: /Users/blacelle/workspace3/cleanthat/java/src/test/java/eu/solven/cleanthat/language/java/rules/test/ATestCases.java
    at sun.nio.fs.UnixException.translateToIOException (UnixException.java:92)
    at sun.nio.fs.UnixException.rethrowAsIOException (UnixException.java:111)
    at sun.nio.fs.UnixException.rethrowAsIOException (UnixException.java:116)
    at sun.nio.fs.UnixFileSystemProvider.newByteChannel (UnixFileSystemProvider.java:219)
    at java.nio.file.Files.newByteChannel (Files.java:370)
    at java.nio.file.Files.newByteChannel (Files.java:421)
    at java.nio.file.Files.readAllBytes (Files.java:3205)
    at com.diffplug.spotless.PaddedCell.calculateDirtyState (PaddedCell.java:189)
    at com.diffplug.spotless.maven.SpotlessApplyMojo.process (SpotlessApplyMojo.java:45)
    at com.diffplug.spotless.maven.AbstractSpotlessMojo.execute (AbstractSpotlessMojo.java:214)
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo (DefaultBuildPluginManager.java:137)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:210)
...

where we try to clean a file whicle it does not exists.

I suppose it relates with the ratchetFrom feature (which is set to origin/main in my configuration).

[nedtwigg]

Fixing this will probably be related to #911

[blacelle]

Also relates with #623