dash 1.19.0 on Python PyPI

Dash and Dash Renderer

#1508 Fix #1403: Adds an x button
to close the error messages box.
#1525 Adds support for callbacks which have overlapping inputs and outputs. Combined with dash.callback_context this addresses many use cases which require circular callbacks.

#1503 Fix #1466: loosen dash[testing] requirements for easier integration in external projects. This PR also bumps many dash[dev] requirements.

#1530 Dedent error messages more carefully.
#1527🐛 get_asset_url now pulls from an external source if assets_external_path is set.
- updated _add_assets_resource to build asset urls the same way as get_asset_url.
- updated doc string for assets_external_path Dash argument to be more clear that it will allways be joined with the assets_url_path argument when determining the url to an external asset.
#1493 Fix #1143, a bug where having a file with one of several common names (test.py, code.py, org.py, etc) that imports a dash component package would make import dash fail with a cryptic error message asking whether you have a file named "dash.py"

#905 Make sure the figure prop of dcc.Graph receives updates from user interactions in the graph, by using the same layout object as provided in the prop rather than cloning it. Fixes #879.
#903 Part of fixing dash import bug #1143

#911, #906
- Upgraded Plotly.js to 1.58.4
  - Patch Release 1.58.4
  - Patch Release 1.58.3

#888 Adds a drag_value prop to dcc.Sliderto be able to fire callbacks from dragging and releasing the slider.