shell and seedling did not build (#1567)

* shell and seedling did not build

(even though CI was green). Time for more CI.

* let's just fix the build in this PR

* Update parachains/runtimes/starters/shell/Cargo.toml

No need to rem this out as we're not testing the new CI changes in this PR.

cumulus/parachains/runtimes/starters/seedling/Cargo.toml

@@ -65,4 +65,5 @@ std = [
 	"cumulus-pallet-solo-to-para/std",
 	"cumulus-primitives-core/std",
 	"parachain-info/std",
+	"parachains-common/std",
 ]

cumulus/parachains/runtimes/starters/shell/Cargo.toml

@@ -74,6 +74,7 @@ std = [
 	"cumulus-primitives-core/std",
 	"cumulus-primitives-utility/std",
 	"parachain-info/std",
+	"parachains-common/std",
 ]
 try-runtime = [
 	"frame-executive/try-runtime",