test/parseconf: Add conf_examples for relays

Tests relay/relay_config.c.

Part of 32213.

src/test/conf_examples/relay_27/torrc

+# Relay tests
+# Options from relay/relay_config.c
+# Relays can't set ReducedCircuitPadding 1
+ORPort 1
+ReducedCircuitPadding 1

src/test/conf_examples/relay_28/error

+SigningKeyLifetime is too short

src/test/conf_examples/relay_28/error_no_dirauth_relay

+This tor was built with relay mode disabled.

src/test/conf_examples/relay_28/torrc

+# Relay tests
+# Options from relay/relay_config.c
+# Short key lifetimes
+ORPort 1
+SigningKeyLifetime 1

src/test/conf_examples/relay_29/error_no_dirauth_relay

+This tor was built with relay mode disabled.

src/test/conf_examples/relay_29/expected

+Nickname Unnamed
+ORPort 1

src/test/conf_examples/relay_29/torrc

+# Relay tests
+# Options from relay/relay_config.c
+# MyFamily normalisation: empty MyFamily
+ORPort 1
+MyFamily