ci: Add tmp pin for conda-libmamba-solver

Author: hoxbro

pixi.toml

@@ -264,6 +264,7 @@ depends-on = ['_docs-generate-rst', '_docs-refmanual', '_docs-generate']
 [feature.build.dependencies]
 python-build = "*"
 conda-build = "*"
+conda-libmamba-solver = "!=25.11.0" # tmp pin https://github.com/conda/conda-libmamba-solver/issues/790
 
 [feature.build.tasks]
 build-conda = 'bash scripts/conda/build.sh'