feat: support extras umap with Python 3.12

#209 introduced support for Python 3.12 with
extras umap not being supported. However, there is in reality nothing preventing umap
from being supported.

The missing support for 3.12 by `umap-learn` was based on a false premise that a new version
of the library needs to be released in order to add support for Python 3.12.

pyproject.toml

@@ -27,7 +27,7 @@ ipywidgets = ">=7.5, <9"
 colorlover = "*"
 scikit-learn = ">=0.22.1"
 nbconvert = "^7.0.0"    # Required for exporting to HTML
-umap-learn = { version = "^0.5.4", optional = true, python = "<3.12"}
+umap-learn = { version = "^0.5.4", optional = true }
 # umap-learn dependes on numba. It is specified explicitly to install
 # a newer version, since by default it installs an older version of numba,
 # which also installs an older version of llmvlite, which is incompatible