Adding multi arch container image generation for magpie and testrp #1942

All 3 278 tests pass, 6 skipped in 3m 57s

3 284 tests +3 284 3 278 ✅ +3 278 3m 57s ⏱️ + 3m 57s
261 suites + 261 6 💤 + 6
1 files + 1 0 ❌ ± 0

Results for commit 87b8946. ± Comparison against earlier commit 57bb341.