Ensure bloom blur size is consistent across hardware scaling levels

[kircher1]

The default rendering pipeline seemed like it was attempting to normalize the bloom blur kernel by the hardware scaling level, but it only took it into account when the hardware scaling level changes at runtime and didn't factor it in upon creation or when constructing the bloom effect itself.

I think the idea to keep the bloom size consistent across different hardware scaling levels is the right idea, but the code needs to change a bit to account for this.

To show the difference:

Starting hardware scale	Before	After
1x	✅	✅
2x	❌	✅

Notice the bottom left before image of 2x scale has a bloom that is much wider and blurrier, rather than matching the 1x scale.

[azure-pipelines]

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[azure-pipelines]

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[Popov72]

Thanks!