fix: semi-transparent colors being forced to full opacity in FlowySvg

[richardshiue]

As an example, hintColor on mobile is not a fully-opaque gray color, but black with its opacity toned down. When passed to FlowySvg, this color's opacity is cranked back up to 1.0. In the sort panel, both the "no active sorts" text and the sort icon specify this hint color but look completely different. In the second example, notice the plus sign next to the words "new row".

Before:

After:

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PR Checklist

• [x] My code adheres to AppFlowy's Conventions
• [ ] I've listed at least one issue that this PR fixes in the description above.
• [ ] I've added a test(s) to validate changes in this PR, or this PR only contains semantic changes.
• [ ] All existing tests are passing.