Rework conda release test: big matrix, no tox involved #1

All 1 060 tests pass, 6 skipped in 2h 17m 32s

25 files + 3 25 suites +3 2h 17m 32s ⏱️ + 1h 23m 40s
1 066 tests ± 0 1 060 ✅ ± 0 6 💤 ± 0 0 ❌ ±0
16 451 runs - 6 869 16 363 ✅ - 6 825 88 💤 - 44 0 ❌ ±0

Results for commit c851641. ± Comparison against earlier commit 8a52a78.