scubainit: Avoid lifetimes on EntFile{Reader,Writer} #180

All 167 tests pass, 2 skipped in 1m 36s

5 files ±0 5 suites ±0 1m 36s ⏱️ -1s
169 tests ±0 167 ✅ ±0 2 💤 ±0 0 ❌ ±0
845 runs ±0 835 ✅ ±0 10 💤 ±0 0 ❌ ±0

Results for commit 4333f41. ± Comparison against earlier commit ce74931.