Update to askama 0.13.0 #461

Job	Run time
Clippy	3m 11s
Build Examples (3d_charts)	31s
Build Wasm Examples (wasm-yew-minimal)	49s
Code Coverage	10s
Build Examples (basic_charts)	31s
Rustfmt	15s
Build Examples (custom_controls)	33s
semver	43s
Build Examples (financial_charts)	29s
Tests (ubuntu-latest)	1m 53s
Tests (windows-latest)	5m 15s
Build Examples (images)	46s
Build Examples (kaleido)	1m 12s
Tests (macos-latest)	1m 52s
Build Examples (maps)	26s
Build Examples (ndarray)	30s
Build Examples (scientific_charts)	29s
Build Examples (shapes)	25s
Build Examples (subplots)	24s
	20m 24s

Provide feedback