support Bar trace 'base' attr #169

Job	Run time
Build Wasm Examples (basic)	59s
Rustfmt	15s
Code Coverage	16s
semver	48s
Tests (ubuntu-latest, chrome, plotly_ndarray,plotly_image,static_export_default,debug)	3m 13s
Build Book	4m 5s
Tests (windows-latest, chrome, plotly_ndarray,plotly_image,static_export_chromedriver,debug)	7m 27s
Tests (ubuntu-latest, firefox, plotly_ndarray,plotly_image,static_export_geckodriver,static_expor...	3m 10s
Clippy	4m 46s
Tests (macos-latest, chrome, plotly_ndarray,plotly_image,static_export_default,debug)	2m 57s
Build Wasm Examples (callback-example)	1m 1s
Build Examples (basic_charts)	34s
Build Examples (custom_controls)	35s
Build Examples (scientific_charts)	34s
Build Examples (themes)	38s
Build Examples (subplots)	33s
Build Examples (customization/multiple_plots_example)	37s
Build Examples (maps)	46s
Build Examples (statistical_charts)	31s
Build Examples (customization/density_mapbox_example)	31s
Build Examples (shapes)	37s
Build Examples (ndarray)	34s
Build Examples (images)	53s
Build Examples (customization/consistent_static_format_export)	1m 44s
Build Examples (kaleido)	1m 16s
Build Examples (3d_charts)	33s
Build Examples (financial_charts)	35s
	40m 28s

Provide feedback