Merge branch 'fix_r-rgsl_build' into 'master'

fix(r-rgsl): build

See merge request technical-coordination/project-internal/devops/platform/ebrains-spack-builds!472

packages/r-rgsl/package.py

@@ -21,3 +21,4 @@ class RRgsl(RPackage):
     # GNU Scientific Library: https://www.gnu.org/software/gsl
     # spack: https://spack.readthedocs.io/en/latest/package_list.html#gsl
     depends_on("gsl")
+    depends_on("pkgconfig")