cargo-pgrx: Call cargo pgrx instead of cargo-pgrx.

The new version check in pgrx 0.11.3 depends on the 'CARGO' environment
variable which is not set unless 'cargo pgrx' is called.

pkgs/development/tools/rust/cargo-pgrx/buildPgrxExtension.nix

@@ -119,7 +119,7 @@ let
 
       NIX_PGLIBDIR="${postgresql}/lib" \
       PGRX_BUILD_FLAGS="--frozen -j $NIX_BUILD_CORES ${builtins.concatStringsSep " " cargoBuildFlags}" \
-      cargo-pgrx pgrx package \
+      cargo pgrx package \
         --pg-config ${postgresql}/bin/pg_config \
         ${maybeDebugFlag} \
         --features "${builtins.concatStringsSep " " buildFeatures}" \