yum: execute rpm command via xargs to avoid the argument length limit

packages/yum/sign-rpm.sh

@@ -28,10 +28,10 @@ done
 
 echo "NOTE: YOU JUST ENTER! YOU DON'T NEED TO INPUT PASSWORD!"
 echo "      IT'S JUST FOR rpm COMMAND RESTRICTION!"
-run rpm \
+run echo $rpms | xargs rpm \
     -D "_gpg_name ${GPG_UID}" \
     -D "_gpg_digest_algo sha1" \
     -D "__gpg /usr/bin/gpg2" \
     -D "__gpg_check_password_cmd /bin/true true" \
     -D "__gpg_sign_cmd %{__gpg} gpg --batch --no-verbose --no-armor %{?_gpg_digest_algo:--digest-algo %{_gpg_digest_algo}} --no-secmem-warning -u \"%{_gpg_name}\" -sbo %{__signature_filename} %{__plaintext_filename}" \
-    --resign $rpms
+    --resign