Stamen Tile Provider migrates to Stadia. Needs update

My workaround:
Make changes in
...\modules\contrib\geolocation\modules\geolocation_leaflet\geolocation_leaflet.libraries.yml

# TileLayer support.
leaflet-providers:
  js:
    'js/leaflet-providers.min.js': {}
  dependencies:
    - geolocation_leaflet/leaflet

Download, update and put leaflet-providers.min.js to ...\modules\contrib\geolocation\modules\geolocation_leaflet\js\
https://cdnjs.cloudflare.com/ajax/libs/leaflet-providers/1.12.0/leaflet-...

leaflet-providers.min.js:

        Stamen: {
-            url: "https://stamen-tiles-{s}.a.ssl.fastly.net/{variant}/{z}/{x}/{y}{r}.{ext}",
+            url: "https://tiles.stadiamaps.com/tiles/{variant}/{z}/{x}/{y}{r}.{ext}",
            options: {
                attribution: 'Map tiles by <a href="http://stamen.com">Stamen Design</a>, <a href="http://creativecommons.org/licenses/by/3.0">CC BY 3.0</a> &mdash; Map data {attribution.OpenStreetMap}',
                subdomains: "abcd",
                minZoom: 0,
                maxZoom: 20,
-                 variant: "toner",
+                variant: "stamen_toner",
                ext: "png"
            },
            variants: {
-                Toner: "toner",
+                Toner: "stamen_toner",
-                TonerBackground: "toner-background",
+               TonerBackground: "stamen_toner-background",
-                TonerHybrid: "toner-hybrid",
+               TonerHybrid: "stamen_toner-hybrid",
-                TonerLines: "toner-lines",
+                TonerLines: "stamen_toner-lines",
-                TonerLabels: "toner-labels",
+                TonerLabels: "stamen_toner-labels",
-                TonerLite: "toner-lite",
+                TonerLite: "stamen_toner-lite",

                Watercolor: {
-                    url: "https://stamen-tiles-{s}.a.ssl.fastly.net/{variant}/{z}/{x}/{y}.{ext}",
+                   url: "https://tiles.stadiamaps.com/tiles/{variant}/{z}/{x}/{y}.{ext}",
                    options: {
-                        variant: "watercolor",
+                      variant: "stamen_watercolor",
                        ext: "jpg",
                        minZoom: 1,
                        maxZoom: 16
                    }
                },
                Terrain: {
                    options: {
-                        variant: "terrain",
+                        variant: "stamen_terrain",
                        minZoom: 0,
                        maxZoom: 18
                    }
                },
                TerrainBackground: {
                    options: {
-                        variant: "terrain-background",
+                        variant: "stamen_terrain-background",
                        minZoom: 0,
                        maxZoom: 18
                    }
                },
                TerrainLabels: {
                    options: {
-                        variant: "terrain-labels",
+                        variant: "stamen_terrain-labels",
                        minZoom: 0,
                        maxZoom: 18
                    }
                },
                TopOSMRelief: {
                    url: "https://stamen-tiles-{s}.a.ssl.fastly.net/{variant}/{z}/{x}/{y}.{ext}",
                    options: {
                        variant: "toposm-color-relief",
                        ext: "jpg",
                        bounds: [
                            [22, -132],
                            [51, -56]
                        ]
                    }
                },
                TopOSMFeatures: {
                    options: {
                        variant: "toposm-features",
                        bounds: [
                            [22, -132],
                            [51, -56]
                        ],
                        opacity: .9
                    }
                }
            }
        },

Update LeafletTileLayerProviders.php in ...\modules\contrib\geolocation\modules\geolocation_leaflet\src\ as described above