[various] Replace deprecated Color.value in SVG packages (#10482)
Replaces the deprecated Color.value with the equivalent toARGB(). While this method is discouraged for many use cases, since it's for interacting with the vector_graphicsColor class, which uses a 32-bit ARGB value as its fundamental representation, this appears to be the correct replacement.
Part of https://github.com/flutter/flutter/issues/159739
## Pre-Review Checklist
[^1]: Regular contributors who have demonstrated familiarity with the repository guidelines only need to comment if the PR is not auto-exempted by repo tooling.
Add svg finder (#880)
* Extract flutter svg to package
* Add flutter svg test library
* Adjust readme
* Update and rename ci.yml to flutter_svg.yml
* Create flutter_svg_test.yml
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Co-authored-by: Dan Field <dfield@gmail.com>