Change YAML syntax to quoted strings

An unexpected behavior arose, and the 3.10 somehow parsed as 3.1.

Signed-off-by: Alex Nelson <alexander.nelson@nist.gov>

Author: ajnelson-nist

.github/workflows/cicd.yml

@@ -23,7 +23,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [ 3.7, 3.10 ]
+        python-version: [ '3.7', '3.10' ]
 
     steps:
     - uses: actions/checkout@v2