One more tweak to Docker image (#335) #39

All 293 tests pass, 20 skipped in 5m 40s

    2 files ±0   20 suites ±0 5m 40s ⏱️ -9s
313 tests ±0 293 ✔️ ±0 20 💤 ±0 0 ❌ ±0
316 runs ±0 296 ✔️ ±0 20 💤 ±0 0 ❌ ±0

Results for commit 51b8ad7. ± Comparison against earlier commit 0784251.