Gradle, CocoaPods: Fix non-compilable dummy header

Issue #KT-39999 fixed

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/native/tasks/CocoapodsTasks.kt

@@ -225,7 +225,7 @@ open class DummyFrameworkTask : DefaultTask() {
         // Copy files for the dummy framework.
         copyFrameworkFile("Info.plist")
         copyFrameworkFile("dummy", frameworkNameProvider.get())
-        copyFrameworkFile("Headers/dummy.h")
+        copyFrameworkFile("Headers/placeholder.h")
         copyFrameworkTextFile("Modules/module.modulemap") {
             if (it == "framework module dummy {") {
                 it.replace("dummy", frameworkNameProvider.get())

libraries/tools/kotlin-gradle-plugin/src/main/resources/cocoapods/dummy.framework/Headers/dummy.h

@@ -1,5 +0,0 @@
-//! Project version number for dummy.
-FOUNDATION_EXPORT double dummyVersionNumber;
-
-//! Project version string for dummy.
-FOUNDATION_EXPORT const unsigned char dummyVersionString[];

libraries/tools/kotlin-gradle-plugin/src/main/resources/cocoapods/dummy.framework/Headers/placeholder.h

@@ -0,0 +1 @@
+// Autogenerated placeholder header. Do not edit manually.

libraries/tools/kotlin-gradle-plugin/src/main/resources/cocoapods/dummy.framework/Modules/module.modulemap

@@ -1,5 +1,5 @@
 framework module dummy {
-  umbrella header "dummy.h"
+  umbrella header "placeholder.h"
 
   export *
   module * { export * }