Improve Ed25519 doctest; improve rand test #122

Job	Run time
GCC 4.8 - CMake 0 - FIPS 0	6m 16s
C-std ubuntu-latest - 11 - Force CMake 0	1m 39s
GCC 7 - CMake 0 - FIPS 0	3m 36s
GCC 4.8 - CMake 0 - FIPS 1	7m 36s
C-std ubuntu-latest - 11 - Force CMake 1	2m 5s
GCC 7 - CMake 0 - FIPS 1	5m 45s
GCC 5 - CMake 0 - FIPS 0	6m 57s
C-std ubuntu-latest - 99 - Force CMake 0	1m 53s
GCC 8 - CMake 0 - FIPS 0	4m 35s
GCC 5 - CMake 0 - FIPS 1	6m 45s
C-std ubuntu-latest - 99 - Force CMake 1	1m 42s
GCC 8 - CMake 0 - FIPS 1	5m 51s
GCC 6 - CMake 0 - FIPS 0	5m 53s
C-std macos-13 - 11 - Force CMake 0	2m 27s
GCC 7 - CMake 1 - FIPS 0	3m 54s
GCC 6 - CMake 0 - FIPS 1	7m 6s
C-std macos-13 - 11 - Force CMake 1	2m 13s
GCC 7 - CMake 1 - FIPS 1	6m 36s
GCC 4.8 - CMake 1 - FIPS 0	5m 46s
GCC 8 - CMake 1 - FIPS 0	4m 10s
C-std macos-13 - 99 - Force CMake 0	3m 48s
GCC 4.8 - CMake 1 - FIPS 1	6m 51s
GCC 8 - CMake 1 - FIPS 1	5m 12s
C-std macos-13 - 99 - Force CMake 1	3m 43s
GCC 5 - CMake 1 - FIPS 0	5m 29s
C-std macos-14-xlarge - 11 - Force CMake 0	1m 35s
GCC 5 - CMake 1 - FIPS 1	7m 0s
C-std macos-14-xlarge - 11 - Force CMake 1	1m 32s
GCC 6 - CMake 1 - FIPS 0	5m 31s
C-std macos-14-xlarge - 99 - Force CMake 0	1m 36s
GCC 6 - CMake 1 - FIPS 1	7m 36s
C-std macos-14-xlarge - 99 - Force CMake 1	1m 29s
C-std windows-latest - 11 - Force CMake 0	4m 2s
C-std windows-latest - 11 - Force CMake 1	3m 48s
C-std windows-latest - 99 - Force CMake 0	3m 33s
C-std windows-latest - 99 - Force CMake 1	3m 50s
	2h 39m 20s

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