build(deps): update dash requirement from <3.5.0 to <4.1.0

Updates the requirements on [dash](https://github.com/plotly/dash) to permit the latest version.
- [Release notes](https://github.com/plotly/dash/releases)
- [Changelog](https://github.com/plotly/dash/blob/dev/CHANGELOG.md)
- [Commits](plotly/dash@v0.18.0...v4.0.0)

---
updated-dependencies:
- dependency-name: dash
  dependency-version: 4.0.0
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

rtd_requirements.txt

@@ -1,4 +1,4 @@
-dash < 3.5.0
+dash < 4.1.0
 demandlib < 0.3.0
 egoio >= 0.4.7, < 0.5.0
 geopy >= 2.0.0, < 2.5.0

setup.py

@@ -33,7 +33,7 @@ def read(fname):
 
 requirements = [
     "contextily < 1.8.0",
-    "dash < 3.5.0",
+    "dash < 4.1.0",
     "demandlib < 0.3.0",
     "descartes < 1.2.0",
     "egoio >= 0.4.7, < 0.5.0",