chore: Add code coverage to `CustomRoyaltyFeeAssessor`, `CustomFixedFeeAssessor` #19813

All 118 859 tests pass, 67 skipped in 3h 47m 24s

2 304 files + 1 2 304 suites +1 3h 47m 24s ⏱️ + 28m 58s
118 926 tests +57 118 859 ✅ +57 67 💤 ±0 0 ❌ ±0
127 487 runs +61 127 420 ✅ +61 67 💤 ±0 0 ❌ ±0

Results for commit 8b1e61d. ± Comparison against earlier commit b41a801.