Cleanup EVP_PKEY serialization #167

Job	Run time
GCC 7 - CMake 0 - FIPS 0	4m 19s
GCC 4.8 - CMake 0 - FIPS 0	5m 9s
GCC 7 - CMake 0 - FIPS 1	5m 8s
GCC 4.8 - CMake 0 - FIPS 1	7m 31s
GCC 8 - CMake 0 - FIPS 0	3m 48s
C-std ubuntu-latest - 11 - Force CMake 0	1m 41s
GCC 5 - CMake 0 - FIPS 0	5m 45s
GCC 8 - CMake 0 - FIPS 1	6m 18s
C-std ubuntu-latest - 11 - Force CMake 1	1m 54s
GCC 5 - CMake 0 - FIPS 1	7m 23s
GCC 7 - CMake 1 - FIPS 0	4m 3s
C-std ubuntu-latest - 99 - Force CMake 0	1m 34s
GCC 6 - CMake 0 - FIPS 0	6m 1s
GCC 7 - CMake 1 - FIPS 1	5m 49s
C-std ubuntu-latest - 99 - Force CMake 1	1m 39s
GCC 6 - CMake 0 - FIPS 1	7m 15s
GCC 4.8 - CMake 1 - FIPS 0	6m 11s
GCC 8 - CMake 1 - FIPS 0	3m 46s
C-std macos-13 - 11 - Force CMake 0	2m 20s
C-std macos-13 - 11 - Force CMake 1	2m 46s
GCC 8 - CMake 1 - FIPS 1	5m 38s
GCC 4.8 - CMake 1 - FIPS 1	9m 25s
C-std macos-13 - 99 - Force CMake 0	2m 0s
GCC 5 - CMake 1 - FIPS 0	6m 46s
GCC 5 - CMake 1 - FIPS 1	7m 10s
C-std macos-13 - 99 - Force CMake 1	2m 43s
GCC 6 - CMake 1 - FIPS 0	5m 46s
C-std macos-14-xlarge - 11 - Force CMake 0	1m 24s
GCC 6 - CMake 1 - FIPS 1	7m 21s
C-std macos-14-xlarge - 11 - Force CMake 1	1m 15s
C-std macos-14-xlarge - 99 - Force CMake 0	1m 28s
C-std macos-14-xlarge - 99 - Force CMake 1	1m 28s
C-std windows-latest - 11 - Force CMake 0	3m 43s
C-std windows-latest - 11 - Force CMake 1	4m 53s
C-std windows-latest - 99 - Force CMake 0	3m 34s
C-std windows-latest - 99 - Force CMake 1	2m 59s
	2h 37m 53s

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