Run SVG files through a normalizer

There is inconsistency between the various SVGs the project uses.

Per https://github.com/microsoft/terminal/pull/9226#pullrequestreview-594682229

> We should probably run these through an SVG normalizer.

There may be other `.svg` files elsewhere in the project, but some are found here:

https://github.com/microsoft/terminal/tree/main/res/terminal

I have no normalizer to suggest.

Review the linked pull request discussion and inventory the SVG files under res/terminal; the issue does not identify a normalizer or complete file set. Select an appropriate normalization approach, apply it to the identified SVGs, and verify that the resulting files are consistent.

Written by the indexing model from the issue text.