Change bowtie2 version to make it work.

.github/workflows/build.yml

@@ -21,7 +21,7 @@ jobs:
     - name: Install dependencies
       run: |
         conda config --add channels bioconda
-        conda install -c conda-forge python=3.9 minimap2 bowtie2 bwa samtools htslib pysam pytest  pytest-cov pylint codecov mappy
+        conda install -c conda-forge python=3.9 minimap2 bowtie2=2.4.5 bwa samtools htslib pysam pytest  pytest-cov pylint codecov mappy
         pip install -Ur requirements.txt
         pip install cooler pytest-pylint
     - name: Lint and test