.github/workflows/dist.yml: Build gmp, mpfr, mpc from SPKG

Author: mkoeppe

.github/workflows/dist.yml

@@ -56,7 +56,7 @@ jobs:
       # SPKGs to install as system packages
       SPKGS: _bootstrap _prereq
       # Non-Python packages to install as spkgs
-      TARGETS_PRE: ppl-ensure gmp-ensure mpfr-ensure mpc-ensure
+      TARGETS_PRE: gmp mpfr mpc ppl-ensure
       # Disable building PyPy wheels on all platforms
       # Disable musllinux until #33083 provides alpine package information
       CIBW_SKIP: "pp* *-musllinux*"