Eradicate ☠ Mono ☠

Co-Authored-By: Gustas <37534529+punkpun@users.noreply.github.com>

.github/ISSUE_TEMPLATE/crash-report.md

@@ -16,7 +16,6 @@ assignees: ''
 - OpenRA Version: ENGINE VERSION
 - OpenRA Mod: GAME MOD
 - Source: Official download package OR self-compiled OR third-party package
-- For self-compiled or third-party packages: Mono version
 
 
 ## Exception log

.github/workflows/ci.yml

@@ -33,24 +33,6 @@ jobs:
           make check-scripts
           make TREAT_WARNINGS_AS_ERRORS=true test
 
-  linux-mono:
-    name: Linux (mono)
-    runs-on: ubuntu-22.04
-
-    steps:
-      - name: Clone Repository
-        uses: actions/checkout@v4
-
-      - name: Check Code
-        run: |
-          mono --version
-          make RUNTIME=mono check
-
-      - name: Check Mods
-        run: |
-          # check-scripts does not depend on .net/mono, so is not needed here
-          make RUNTIME=mono TREAT_WARNINGS_AS_ERRORS=true test
-
   windows:
     name: Windows (.NET 6.0)
     runs-on: windows-2019