Standardize terminology: only `restricted environments` and no `air gap

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nickboldt added a comment
My poins is we're being inconsistent with the terminology:

• https://access.redhat.com/documentation/en-us/red_hat_openshift_dev_spaces/3.1/html-single/release_notes_and_known_issues/index - 9 occurrences of "restricted environment"; 0 "air-gap"
• https://access.redhat.com/documentation/en-us/red_hat_openshift_dev_spaces/3.1/html-single/administration_guide/index - 7 occurrences of "restricted environment"; 0 "air-gap"
• https://access.redhat.com/documentation/en-us/red_hat_openshift_dev_spaces/3.1/html-single/user_guide/index - 10 occurrences of "restricted environment"; 2 "air-gap"

Restricted environment is the generic term for "behind a proxy, fully- or partially-disconnected from the internet". "Air-gap" is a more colloquial term which implies fully disconnected, and could therefore imply that proxied, mirrored, or partially disconnected envs are not applicable.

Perhaps there's an IBM Style Guide you could refer to here? rkratky@redhat.com can probably point you at the official terminology to use.

https://issues.redhat.com/browse/CRW-3373?focusedCommentId=21071637&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-21071637