UnboundLocalError when decomposing multiallelic variants

[Schmytzi]

Describe the bug
Stranger crashes with an UnboundLocalError when encountering a multiallelic variant where the first sample does not have allele 1.

To Reproduce
Run

stranger --trgt broken_repeat.vcf --repeats-file variant_catalog_grch38.json

broken_repeat.vcf is attached here:
broken_repeat.zip

The variant catalog is the following: https://github.com/Clinical-Genomics/stranger/raw/main/stranger/resources/stranger_repeat_catalog_grch38.json

Expected behavior
Stranger should correctly decompose and annotate the variant (or in this case: emit a warning about the unknown repeat)

System:

• OS: Linux (Red Hat Enterprise Linux 8.10)
• Environment: Running in Apptainer (Container: https://depot.galaxyproject.org/singularity/stranger:0.9.2--pyh7e72e81_0)
• Version: 0.9.2

Additional context
The crash does not occur if you switch the individuals' genotypes. Then stranger works correctly.