Update dependency org.springframework:spring-core to v5.3.39 #375

All 144 177 tests pass in 2m 2s

144 177 tests ±0 144 177 ✔️ ±0 2m 2s ⏱️ +2s
        24 suites ±0           0 💤 ±0
        24 files ±0           0 ❌ ±0

Results for commit 6193cef. ± Comparison against earlier commit 09ec10c.