modify CI badge and link

Author: rrsettgast

README.md

@@ -1,7 +1,7 @@
 HPCReact
 
 [![DOI](https://zenodo.org/badge/880512605.svg)](https://doi.org/10.5281/zenodo.15743474)
-[![CI](https://github.com/GEOS-DEV/HPCReact/actions/workflows/continuousIntegration.yml/badge.svg)]
+[![CI](https://github.com/GEOS-DEV/HPCReact/actions/workflows/continuousIntegration.yml/badge.svg?branch=main)](https://github.com/GEOS-DEV/HPCReact/actions/workflows/continuousIntegration.yml?query=branch%3Amain)
 [![codecov](https://codecov.io/github/geos-dev/hpcreact/graph/badge.svg?token=VMYDFYCT3Q)](https://codecov.io/github/geos-dev/hpcreact)
 
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