Need meta.COMMIT_DISTANCE_TO_ROOT exposed as a Maven property

## Issue

**version**: 1.9.0

**usage context**: `mvn validate`

- [x] maven command line: 3.8.5

**Problem description**:

Using strategy=PATTERN and defining in the `jgitver.config.xml`:
```
${v}${-~meta.QUALIFIED_BRANCH_NAME}${+~meta.COMMIT_DISTANCE_TO_ROOT}
```
Never results in the the `COMMIT_DISTANCE_TO_ROOT` property being populated, even when `useCommitDistance` is `true`.

How to get this information into a Maven property?