fix: [FX-2626] set up danger env variable for self-hosted runners (#128)

* fix: set up danger env variable for self-hosted runners

* chore: add changeset

* chore: update copies

* chore: update copies

* chore: update copies

Author: dmaklygin

.changeset/update.md

@@ -0,0 +1,7 @@
+---
+'davinci-github-actions': patch
+---
+
+---
+
+- set the `danger` environment variable to ensure that all API requests are performed on the correct domain

danger/action.yml

@@ -5,4 +5,10 @@ runs:
   using: composite
   steps:
     - shell: bash
+      env:
+        # Self-hosted runners can override the GITHUB_URL environment variable
+        # to a potentially incorrect value, and this variable may also be used
+        # for other purposes beyond communicating with the GitHub API. 
+        # The DANGER_GITHUB_API_BASE_URL env variable takes higher priority 
+        DANGER_GITHUB_API_BASE_URL: https://api.github.com
       run: yarn davinci-ci danger