Properly drop overwritten ex data #624

Job	Run time
Test FIPS integration	2m 55s
Cross build from macOS to Linux (x86_64-unknown-linux-gnu)	4m 4s
clippy	1m 2s
Cross build from macOS to Linux (FIPS) (x86_64-unknown-linux-gnu)	6m 27s
rustfmt	12s
Test features	3m 14s
Test (stable)	2m 18s
Test (macos-x86_64)	5m 48s
Test (arm-android)	2m 1s
Test (arm64-android)	2m 4s
Test (i686-android)	2m 7s
Test (x86_64-android)	2m 3s
Test (aarch64-ios)	3m 43s
Test (aarch64-ios-sim)	2m 44s
Test (x86_64-ios)	5m 8s
Test (i686-linux)	2m 14s
Test (arm-linux)	2m 8s
Test (aarch64-linux)	2m 2s
Test (x86_64-musl)	2m 5s
Test (x86_64-mingw)	2m 4s
Test (i686-msvc)	5m 25s
Test (x86_64-msvc)	5m 24s
	1h 7m 12s

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