Fix coverity issues on branch 8.4 #410

Job	Run time
basic_clang	12s
basic_gcc	18s
check-ansi	2m 1s
address_ub_sanitizer	11m 6s
check_update	1m 2s
enable_non-default_options	21s
fips_and_ktls	17s
memory_sanitizer	21m 2s
minimal	2m 13s
no-deprecated	17s
no-legacy	16s
non-caching	4m 20s
no-shared (ubuntu-latest)	16s
ntls_address_ub_sanitizer	9m 49s
no-shared (macos-latest)	2m 26s
ntls_memory_sanitizer	17m 16s
threads_sanitizer	10s
buildtest	6m 52s
EC_POINTs_api_test	19m 15s
external-test-pyca (1.51.0, 3.9)	1m 23s
legacy	3m 31s
ntls	13s
ntls-with-fips	17s
ntls-without-sm234	19s
out-of-source-and-install (ubuntu-latest)	17s
phe_test	13s
out-of-source-and-install (macos-latest)	3m 12s
symbol_prefix-test	1m 16s
zkp-build-test	10s
	1h 50m 20s

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