switch to Bing Maps API for Bing Streetside layer, fixes #10074

replaces the use of undocumented APIs for Microsoft's street level imagery service and gets rid of hardcoded values, e.g. for the `g` ("generation") parameter

see https://learn.microsoft.com/en-us/bingmaps/rest-services/imagery/get-imagery-metadata#get-streetside-metadata-centered-at-a-point for API docs

see also #10100

modules/util/jsonp_request.js

@@ -1,61 +0,0 @@
-import { select as d3_select } from 'd3-selection';
-
-var jsonpCache = {};
-window.jsonpCache = jsonpCache;
-
-export function jsonpRequest(url, callback) {
-    var request = {
-        abort: function() {}
-    };
-
-    if (window.JSONP_FIX) {
-        if (window.JSONP_DELAY === 0) {
-            callback(window.JSONP_FIX);
-        } else {
-            var t = window.setTimeout(function() {
-                callback(window.JSONP_FIX);
-            }, window.JSONP_DELAY || 0);
-
-            request.abort = function() { window.clearTimeout(t); };
-        }
-
-        return request;
-    }
-
-    function rand() {
-        var chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';
-        var c = '';
-        var i = -1;
-        while (++i < 15) c += chars.charAt(Math.floor(Math.random() * 52));
-        return c;
-    }
-
-    function create(url) {
-        var e = url.match(/callback=(\w+)/);
-        var c = e ? e[1] : rand();
-
-        jsonpCache[c] = function(data) {
-            if (jsonpCache[c]) {
-                callback(data);
-            }
-            finalize();
-        };
-
-        function finalize() {
-            delete jsonpCache[c];
-            script.remove();
-        }
-
-        request.abort = finalize;
-        return 'jsonpCache.' + c;
-    }
-
-    var cb = create(url);
-
-    var script = d3_select('head')
-        .append('script')
-        .attr('type', 'text/javascript')
-        .attr('src', url.replace(/(\{|%7B)callback(\}|%7D)/, cb));
-
-    return request;
-}