Add a sed utility

[DavidHuber-NOAA]

Description This creates a utility to build a sed search/replace command and pipe the output to another file.

Type of change

• [x] New feature (non-breaking change which adds functionality)
• [x] This change requires a documentation update

How Has This Been Tested?

• [x] pynorms
• [x] pytests

Checklist

• [x] My code follows the style guidelines of this project
• [x] I have performed a self-review of my own code
• [x] I have commented my code, particularly in hard-to-understand areas
• [x] My changes need updates to the documentation. I have made corresponding changes to the documentation
• [x] My changes generate no new warnings
• [x] New and existing tests pass with my changes

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 88.88889% with 2 lines in your changes are missing coverage. Please review.

Project coverage is 49.21%. Comparing base (63db259) to head (fb0c04d).

Files	Patch %	Lines
src/wxflow/file_utils.py	88.88%	1 Missing and 1 partial :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## develop #23 +/- ## =========================================== + Coverage 47.99% 49.21% +1.22% =========================================== Files 18 18 Lines 1642 1660 +18 Branches 330 334 +4 =========================================== + Hits 788 817 +29 + Misses 798 787 -11 Partials 56 56 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.