UW-510 Add uw template render --partial switch

[maddenp-noaa]

Synopsis

A new --partial flag for the uw template render mode/action permits partial rendering of templates, i.e., unrenderable values are passed through unchanged and without error.

Old behavior:

% echo "{{ greeting }} {{ recipient }}" | greeting=Hello uw template render
[2024-02-27T22:19:18]    ERROR Required value(s) not provided:
[2024-02-27T22:19:18]    ERROR recipient

New behavior:

% echo "{{ greeting }} {{ recipient }}" | greeting=Hello uw template render --partial
Hello {{ recipient }}

Type

• Documentation
• Enhancement (adds a new functionality)

Impact

• This is a non-breaking change (existing functionality continues to work as expected)

Checklist

• I have added myself and any co-authors to the PR's Assignees list.
• I have reviewed the documentation and have made any updates necessitated by this change.

[christinaholtNOAA]

LGTM. Happy with whatever you decide on the question below.