Update reqwest requirement from 0.12 to 0.13 #130

Job	Run time
semver	51s
Code Coverage	10s
Clippy	4m 32s
Build Wasm Examples (basic)	56s
Build Book	3m 47s
Rustfmt	15s
Build Wasm Examples (callback-example)	58s
Tests (macos-latest, chrome, plotly_ndarray,plotly_image,static_export_default,debug)	3m 15s
Tests (ubuntu-latest, firefox, plotly_ndarray,plotly_image,static_export_geckodriver,static_expor...	3m 24s
Tests (ubuntu-latest, chrome, plotly_ndarray,plotly_image,static_export_default,debug)	3m 14s
Tests (windows-latest, chrome, plotly_ndarray,plotly_image,static_export_chromedriver,debug)	6m 49s
Build Examples (maps)	42s
Build Examples (kaleido)	1m 26s
Build Examples (financial_charts)	43s
Build Examples (customization/consistent_static_format_export)	1m 42s
Build Examples (custom_controls)	33s
Build Examples (scientific_charts)	30s
Build Examples (customization/density_mapbox_example)	26s
Build Examples (subplots)	25s
Build Examples (themes)	32s
Build Examples (statistical_charts)	34s
Build Examples (images)	49s
Build Examples (customization/multiple_plots_example)	34s
Build Examples (basic_charts)	28s
Build Examples (ndarray)	34s
Build Examples (shapes)	34s
Build Examples (3d_charts)	38s
	39m 21s

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