Add Pie Chart trace #418

Job	Run time
Build Wasm Examples (wasm-yew-minimal)	48s
Code Coverage	1m 54s
Build Examples (3d_charts)	23s
Clippy	3m 3s
Build Examples (basic_charts)	28s
Rustfmt	11s
semver	1m 20s
Build Examples (custom_controls)	23s
Tests (ubuntu-latest)	1m 48s
Build Examples (financial_charts)	22s
Tests (windows-latest)	4m 50s
Build Examples (images)	35s
Tests (macos-latest)	2m 1s
Build Examples (kaleido)	1m 10s
Build Examples (maps)	24s
Build Examples (ndarray)	22s
Build Examples (scientific_charts)	33s
Build Examples (shapes)	32s
Build Examples (subplots)	24s
	21m 31s

Provide feedback