REGTESTS: fix quoting in feature cmd which prevents test execution

Remove extra quote in feature cmd used to test SSL compatibility with
set_ssl_cafile QUIC regtest. Due to this syntax error, the test was
never executed.

No need to backport.

Author: a-denoyelle

reg-tests/quic/set_ssl_cafile.vtc

@@ -15,7 +15,7 @@
 # - Check that you have socat
 
 varnishtest "Test the 'set ssl ca-file' feature of the CLI"
-feature cmd "$HAPROXY_PROGRAM -cc 'feature(QUIC) && !feature(QUIC_OPENSSL_COMPAT) && !feature(OPENSSL_WOLFSSL)' && !feature(OPENSSL_AWSLC)'"
+feature cmd "$HAPROXY_PROGRAM -cc 'feature(QUIC) && !feature(QUIC_OPENSSL_COMPAT) && !feature(OPENSSL_WOLFSSL) && !feature(OPENSSL_AWSLC)'"
 
 feature cmd "command -v socat"