ci: build and cache more packages in the Nix CI workflow

Author: jfroche

flake.nix

@@ -1379,7 +1379,7 @@
           psql_15 = makeCheckHarness basePackages.psql_15.bin;
           psql_17 = makeCheckHarness basePackages.psql_17.bin;
           psql_orioledb-17 = makeCheckHarness basePackages.psql_orioledb-17.bin;
-          inherit (basePackages) wal-g-2 wal-g-3;
+          inherit (basePackages) wal-g-2 wal-g-3 dbmate-tool pg_regress;
         } // pkgs.lib.optionalAttrs (system == "aarch64-linux") {
           inherit (basePackages) postgresql_15_debug postgresql_15_src postgresql_orioledb-17_debug postgresql_orioledb-17_src postgresql_17_debug postgresql_17_src;
         };
@@ -1455,6 +1455,7 @@
                 dbmate
                 nushell
                 pythonEnv
+                nix-fast-build
               ];
               shellHook = ''
                 export HISTFILE=.history