fix maps examples #84

Job	Run time
Clippy	4m 20s
Rustfmt	17s
Code Coverage	14s
Tests (ubuntu-latest, chrome, plotly_ndarray,plotly_image,static_export_default,debug)	3m 13s
semver	44s
Tests (windows-latest, chrome, plotly_ndarray,plotly_image,static_export_chromedriver,debug)	6m 58s
Tests (macos-latest, chrome, plotly_ndarray,plotly_image,static_export_default,debug)	4m 38s
Build Wasm Examples (basic)	53s
Build Book	3m 48s
Build Wasm Examples (callback-example)	49s
Tests (ubuntu-latest, firefox, plotly_ndarray,plotly_image,static_export_geckodriver,static_expor...	3m 8s
Build Examples (basic_charts)	27s
Build Examples (financial_charts)	33s
Build Examples (customization/consistent_static_format_export)	1m 19s
Build Examples (customization/multiple_plots_example)	27s
Build Examples (customization/density_mapbox_example)	35s
Build Examples (custom_controls)	28s
Build Examples (3d_charts)	25s
Build Examples (kaleido)	1m 52s
Build Examples (images)	41s
Build Examples (subplots)	26s
Build Examples (themes)	25s
Build Examples (maps)	44s
Build Examples (shapes)	33s
Build Examples (scientific_charts)	27s
Build Examples (ndarray)	33s
Build Examples (statistical_charts)	31s
	39m 28s

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