CLI-19: [self-update] respect proxy settings

Author: danepowell

composer.json

@@ -11,13 +11,19 @@
         }
     ],
     "minimum-stability": "dev",
+    "repositories": [
+        {
+            "type": "vcs",
+            "url": "https://github.com/danepowell/self-update"
+        }
+    ],
     "require": {
         "php": "^8.1",
         "ext-json": "*",
         "acquia/drupal-environment-detector": "^1.2.0",
         "bugsnag/bugsnag": "^3.0",
         "composer/semver": "^3.3",
-        "consolidation/self-update": "^2.1.0",
+        "consolidation/self-update": "dev-CLI-19 as 2.1.0",
         "dflydev/dot-access-data": "^3",
         "grasmash/expander": "^3",
         "guzzlehttp/guzzle": "^7.4",