Add GitHub action to build GCPy environment with micromamba

.github/workflows/micromamba.yml
- YAML file to tell GitHub Actions to build the GCPy python environment
  and then try to make a test plot.  Checks for proper installation.
  NOTE: Further testing/revisions may be needed.

CHANGELOG.md
- Updated accordingly.

Signed-off-by: Bob Yantosca <[email protected]>

.github/workflows/micromamba.yml

@@ -0,0 +1,16 @@
+#
+# GitHub action to build the GCPy environment with micromamba
+# See: https://github.com/marketplace/actions/setup-micromamba
+#
+- uses: mamba-org/[email protected]
+  with:
+    micromamba-version: "latest"
+    environment-file: "environment.yml"
+    init-shell: >-
+      bash
+    cache-environment: true
+    post-cleanup: "all"
+
+- name: Import numpy in micromamba environment (bash)
+  run: python -c "python -c gcpy.example.plotting.create_test_plot"
+  shell: bash -el {0}

CHANGELOG.md

@@ -10,6 +10,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 
 ## [1.4.1] - 2023-12-08
+### Added
+- GitHub action script `micromamba.yml`: Builds the environment in `environment.yml` and tries to make a test plot
+
 ### Fixed
 - Now use the proper default value for the `--weightsdir` argument to `gcpy/file_regrid.py`