Fix pytest-html to 3.2.0 otherwise plotly wont work #1534

All 251 tests pass, 1 006 skipped in 4m 10s

1 257 tests - 142   251 ✔️ -     1 4m 10s ⏱️ - 5m 0s
      1 suites ±    0 1 006 💤 - 141
      1 files ±    0       0 ❌ ±    0

Results for commit e2adae5. ± Comparison against earlier commit 7b831d4.