Introduce snapshot unit tests for `re_component_ui` #15658

Job	Run time
paths-filter	6s
Checks / markdown-paths-filter	10s
Checks / Lint markdown	17s
Checks / Misc formatting	15s
Checks / Rerun lints	39s
Checks / Check if running codegen would produce any changes	1m 22s
Checks / Spell Check	9s
Deploy Landing Preview	0s
C++ tests	0s
Python Checks	0s
Build web viewer / Build web viewer	3m 24s
Rust Checks / Test on ${{ matrix.name }}	0s
Build rerun_js / Build rerun_js	3m 29s
Minimum CLI Build / Set Config (linux-x64)	2s
Rust Checks / Rust lints (fmt, check, clippy, tests, doc)	5m 15s
Checks / Check links	0s
Minimum CLI Build / Build rerun-cli (ubuntu-latest-16-cores)	5m 39s
Upload Web / Upload web build to google cloud (wasm32 + wasm-bindgen)	11s
Minimum Wheel Build / Set Config (linux-x64)	2s
Minimum Wheel Build / Build Wheels (ubuntu-latest-16-cores)	2m 14s
Minimum Wheel Test / Set Config (linux-x64)	2s
Minimum Wheel Test / Test Wheels (ubuntu-latest-16-cores)	3m 25s
	26m 41s

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