Drop repoman in favour of pkgcheck/pkgdev

As per discussed in [1]

[1] https://archives.gentoo.org/gentoo-dev/message/93df9e7a2ad9d8d33e0cc83b50556d51

Signed-off-by: Andrew Ammerlaan <andrewammerlaan@gentoo.org>

.github/workflows/repoman.yml

@@ -1,19 +0,0 @@
-name: repoman
-
-on:
-  push:
-    branches: [ dev ]
-  pull_request:
-    branches: [ dev ]
-
-jobs:
-  build:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - name: Setup master gentoo repository
-      run: |
-        ./scripts/setup-master-gentoo.sh
-    - name: Setup and run Repoman
-      run: |
-        ./scripts/setup-and-run-repoman.sh