[Fix] missing leading slash on datasetname

[claudiushaag]

This fixes #96 , which was noticed by multiple people now :D
I added a "regression" test using pytest, as this was the slimmest version I could think of/find. Unit-testing Reader ::ReadInputFile is difficult due to the exit(10) at the end and the MPI constructions. An atomic unit-test using a proper framework would be for a newly introduced submethod normalize_datasetname(), but I opted out of that for readability etc, as it seemed like an overkill, even though it being the "correct" and future-proof method.

I also fixed a german problem on run_test.sh, because the different locale interfered with bc in the script.

Pre-Commit does not run currently, no luck with cleaning or something else.

Traceback (most recent call last):
  File "/scratch/local/XXX/Code/FANS/.pixi/envs/default/bin/pre-commit", line 6, in <module>
    from pre_commit.main import main
  File "/scratch/local/XXX/Code/FANS/.pixi/envs/default/lib/python3.14/site-packages/pre_commit/main.py", line 14, in <module>
    from pre_commit.commands.clean import clean
  File "/scratch/local/XXX/Code/FANS/.pixi/envs/default/lib/python3.14/site-packages/pre_commit/commands/clean.py", line 6, in <module>
    from pre_commit.store import Store
  File "/scratch/local/XXX/Code/FANS/.pixi/envs/default/lib/python3.14/site-packages/pre_commit/store.py", line 6, in <module>
    import sqlite3
  File "/scratch/local/XXX/Code/FANS/.pixi/envs/default/lib/python3.14/sqlite3/__init__.py", line 57, in <module>
    from sqlite3.dbapi2 import *
  File "/scratch/local/XXX/Code/FANS/.pixi/envs/default/lib/python3.14/sqlite3/dbapi2.py", line 27, in <module>
    from _sqlite3 import *
ImportError: /scratch/local/XXX/Code/FANS/.pixi/envs/default/lib/python3.14/lib-dynload/_sqlite3.cpython-314-x86_64-linux-gnu.so: undefined symbol: sqlite3_deserialize

Checklist:

• I made sure that the CI passed before I ask for a review.
• I added a summary of the changes (compared to the last release) in the CHANGELOG.md.
• If necessary, I made changes to the documentation and/or added new content.
• I will remember to squash-and-merge, providing a useful summary of the changes of this PR.

[sanathkeshav]

@claudiushaag, this is too trivial and does not need any regression test or such. We will just check and patch it.

[claudiushaag]

I just noticed that I relocked the lock-file, therefore the update for some higher build-numbers - I can also roll that back if prefered :)