Adds MetadataHash calculation on Build to Kusama People chain (#371)

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This adds the calculation of the MetadataHash upon build in the Kusama
People Chains Runtime. I don't think this needs a CHANGELOG entry, but I
could be mistaken.

---------

Co-authored-by: Bastian Köcher <[email protected]>

CHANGELOG.md

@@ -129,6 +129,10 @@ Note: This release only affects the following runtimes and is not a full system
 - Kusama Relay Chain
 - Kusama Bridge Hub
 
+### Fixed
+
+- Kusama People: Build the metadata hash at build time, so that `CheckMetadata` can use it at runtime ([polkadot-fellows/runtimes#371](https://github.com/polkadot-fellows/runtimes/pull/371))
+
 ## [1.2.7] 14.06.2024
 
 Note: This release only affects the following runtimes and is not a full system release:

system-parachains/people/people-kusama/build.rs

@@ -13,12 +13,15 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#[cfg(feature = "std")]
+#[cfg(all(feature = "std", not(feature = "metadata-hash")))]
 fn main() {
-	substrate_wasm_builder::WasmBuilder::new()
-		.with_current_project()
-		.export_heap_base()
-		.import_memory()
+	substrate_wasm_builder::WasmBuilder::build_using_defaults()
+}
+
+#[cfg(all(feature = "std", feature = "metadata-hash"))]
+fn main() {
+	substrate_wasm_builder::WasmBuilder::init_with_defaults()
+		.enable_metadata_hash("KSM", 12)
 		.build()
 }