Explicit types arguments instead of reified intersection for 2.3.0-Beta1 (#4514)

Reified intersection type arguments are currently a warning (KT-52469)
but will soon become an error (KT-71420).

Author: bnorm

kotlinx-coroutines-core/common/test/flow/operators/CombineParametersTest.kt

@@ -70,7 +70,7 @@ class CombineParametersTest : TestBase() {
 
     @Test
     fun testVararg() = runTest {
-        val flow = combine(
+        val flow = combine<Any?, String>(
             flowOf("1"),
             flowOf(2),
             flowOf("3"),
@@ -83,7 +83,7 @@ class CombineParametersTest : TestBase() {
 
     @Test
     fun testVarargTransform() = runTest {
-        val flow = combineTransform(
+        val flow = combineTransform<Any?, String>(
             flowOf("1"),
             flowOf(2),
             flowOf("3"),