Upgrade echarts and vue-echarts & Add fallback for visualMap when using heatmap

[florian-h05]

This upgrades echarts and vue-echarts to the latest versions.
@vue/composition-api was added as dependency because vue-echarts needs it on Vue 2.

See https://echarts.apache.org/handbook/en/basics/release-note/v5-upgrade-guide/ and https://github.com/ecomfe/vue-echarts#migration-to-v6 for upgrade guides.

This also adds a fallback default for visualMap because it is required to define a visualMap when using a heatmap, otherwise echarts fails to render the chart.
Even though the docs and the chart-designer mentioned this until now, it worked without defining a visualmap, which would not be the case anymore (and therefore break charts - defining a visual map is easy though) without providing a fallback.

[relativeci]

Job #1807: Bundle Size — 11.15MiB (+0.2%).

d31bbed(current) vs 1ceb5c6 main#1804(baseline)

Warning

Bundle contains 19 duplicate packages – View duplicate packages

Warning

Bundle introduced 2 new packages: vue-demi, @vue/composition-api – View changed packages

Bundle metrics   8 changes 1 regression 3 improvements

	Current Job #1807	Baseline Job #1804
Initial JS	1.84MiB(~-0.01%)	1.84MiB
Initial CSS	607.88KiB	607.88KiB
Cache Invalidation	18.73%	17.13%
Chunks	219(-0.45%)	220
Assets	242(-0.41%)	243
Modules	3051(-1.33%)	3092
Duplicate Modules	144(-12.2%)	164
Duplicate Code	1.69%(-3.43%)	1.75%
Packages	153(+1.32%)	151
Duplicate Packages	18	18

Bundle size by type   2 changes 1 regression 1 improvement

	Current Job #1807	Baseline Job #1804
JS	9.34MiB (+0.24%)	9.32MiB
CSS	889.25KiB (-0.01%)	889.35KiB
Fonts	526.1KiB	526.1KiB
Media	295.6KiB	295.6KiB
IMG	140.74KiB	140.74KiB
HTML	1.24KiB	1.24KiB
Other	871B	871B

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View job #1807 report View florian-h05:upgrade-echarts branch activity View project dashboard

[stefan-hoehn]

I tested it on my side. Even though openHAB charts seem to work, the network chart in the Z-Wave plugin does not. The latter doesn't even through an exception in the logs or anything obvious shows up in the console.

[stefan-hoehn]

I can confirm that it works now as it should. Looks good to me overall. Hope I have not overseen something.