Attempt 4 to get CI working on Mac

Makefile

@@ -1,11 +1,8 @@
 PACKAGE_NAME := red
 PACKAGE_DIR  := red
 
-# Required to get things working on MacOS GitHub CI
-SHELL_SETUP = source ~/.bashrc && source ~/.bash_profile
-
-# If we're running in GitHub Actions, we need to use micromamba instead of conda and activate the environment
-CONDA_ENV_RUN   = $(if $(GITHUB_ACTIONS),$(SHELL_SETUP) && micromamba run -n $(PACKAGE_NAME),conda run --no-capture-output --name $(PACKAGE_NAME))
+# If we're running in GitHub Actions, we need to use micromamba instead of conda
+CONDA_ENV_RUN   = $(if $(GITHUB_ACTIONS),bash -l -c 'micromamba run -n $(PACKAGE_NAME)',conda run --no-capture-output --name $(PACKAGE_NAME))
 
 TEST_ARGS := -v --cov=$(PACKAGE_NAME) --cov-report=term --cov-report=xml --junitxml=unit.xml --color=yes