Resolve X25519 handshake problem #1173

Job	Run time
check_update	54s
basic_clang	4m 9s
basic_gcc	4m 18s
check-ansi	2m 7s
minimal	2m 9s
no-deprecated	3m 54s
non-caching	4m 14s
no-shared (ubuntu-latest)	3m 20s
address_ub_sanitizer	10m 55s
no-shared (macos-latest)	4m 2s
enable_non-default_options	3m 37s
fips_and_ktls	4m 10s
legacy	3m 42s
memory_sanitizer	25m 42s
no-legacy	4m 27s
ntls_address_ub_sanitizer	9m 32s
ntls_memory_sanitizer	18m 0s
symbol_prefix-test	7m 1s
threads_sanitizer	3m 35s
buildtest	6m 45s
EC_POINTs_api_test	18m 34s
external-test-pyca (1.51.0, 3.9)	1m 24s
ntls	44m 7s
ntls-with-fips	7m 53s
ntls-without-sm234	6m 47s
out-of-source-and-install (ubuntu-latest)	4m 21s
out-of-source-and-install (macos-latest)	7m 10s
phe_test	35m 53s
zkp-build-test	3m 15s
	4h 15m 57s

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