FAPI: Fix usage of external PEM keys for PolicyAuthorize. 3.2.x #2156

Job	Run time
scanbuild	11m 14s
test-mbedtls (ubuntu-20.04)	2m 56s
build-test (ubuntu-20.04, gcc)	4m 30s
test-mbedtls (ubuntu-22.04-mbedtls-3.1)	2m 39s
build-test (ubuntu-20.04, clang)	4m 2s
coverity-test	0s
build-test (fedora-32, gcc)	4m 52s
test-coverage	4m 58s
build-test (fedora-32, clang)	4m 37s
test-fuzz	2m 23s
build-test (opensuse-leap, gcc)	4m 33s
build-test (opensuse-leap, clang)	4m 19s
test-tcti-config	10m 36s
	1h 1m 39s

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