update code of conduct per guidance from NASA

CODE_OF_CONDUCT.md

@@ -1,17 +1,12 @@
-
 # Contributor Covenant Code of Conduct
 
 ## Our Pledge
 
 We as members, contributors, and leaders pledge to make participation in our
-community a harassment-free experience for everyone, regardless of age, body
-size, visible or invisible disability, ethnicity, sex characteristics, gender
-identity and expression, level of experience, education, socio-economic status,
-nationality, personal appearance, race, religion, or sexual identity
-and orientation.
+community a harassment-free experience for everyone.
 
 We pledge to act and interact in ways that contribute to an open, welcoming,
-diverse, inclusive, and healthy community.
+and healthy community.
 
 ## Our Standards