Overriding placeholder version in updatable apks

Test: presubmit, checked the app version after build locally
Bug: 231691162
Change-Id: Icd242432540ea424235b226a45aac839dbc995be

java/app.go

@@ -417,6 +417,9 @@ func (a *AndroidApp) aaptBuildActions(ctx android.ModuleContext) {
 
 	a.aapt.splitNames = a.appProperties.Package_splits
 	a.aapt.LoggingParent = String(a.overridableAppProperties.Logging_parent)
+	if a.Updatable() {
+		a.aapt.defaultManifestVersion = android.DefaultUpdatableModuleVersion
+	}
 	a.aapt.buildActions(ctx, android.SdkContext(a), a.classLoaderContexts,
 		a.usesLibraryProperties.Exclude_uses_libs, aaptLinkFlags...)