Fix /beta page showing no uplifts: use & not & in hg URLs

The hg.mozilla.org/hg-edge.mozilla.org backend recently tightened its
query-string parsing and no longer tolerates HTML-encoded separators.
With &, only `fromchange` reached the server, so `version=2` was
dropped and responses came back in the v1 shape (push IDs at the top
level) without the `pushes` key getBugsFromHgWeb() expects, yielding
the empty `no_data: true` stub for every beta.

Mirrors the equivalent guard already in ReleaseUpliftsTest.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: pascalchevrel

app/classes/ReleaseInsights/Beta.php

@@ -94,9 +94,9 @@ public function getLogEndpoints(): array
             $hg_end_points[$beta_version] =
                 'releases/mozilla-beta/json-pushes?fromchange='
                 . $beta_start
-                . '&tochange='
+                . '&tochange='
                 . $beta_end
-                . '&full&version=2';
+                . '&full&version=2';
         }
 
         /*
@@ -125,9 +125,9 @@ public function getLogEndpoints(): array
                 $hg_end_points[$rc_version] =
                     'releases/mozilla-release/json-pushes?fromchange='
                     . $rc_start
-                    . '&tochange='
+                    . '&tochange='
                     . $rc_end
-                    . '&full&version=2';
+                    . '&full&version=2';
             }
         }
 

tests/Unit/ReleaseInsights/BetaTest.php

@@ -18,6 +18,18 @@
         ->each->toBeString();
 });
 
+test('Beta->getLogEndpoints() URLs use & not &', function () {
+    $obj = new Beta();
+    $endpoints = $obj->getLogEndpoints();
+
+    expect($endpoints)->toBeArray()->not->toBeEmpty();
+
+    foreach ($endpoints as $url) {
+        expect($url)->not->toContain('&');
+        expect($url)->toContain('&');
+    }
+});
+
 test('Beta->crashes()', function () {
     $obj = new Beta();
     expect($obj->crashes())