[isoltest] Extract event specific end-to-end tests.

test/libsolidity/semanticTests/events/event_dynamic_array_storage.sol

@@ -0,0 +1,20 @@
+contract C {
+    event E(uint[]);
+    uint[] arr;
+    function createEvent(uint x) public {
+        while (arr.length < 3)
+            arr.push();
+        arr[0] = x;
+        arr[1] = x + 1;
+        arr[2] = x + 2;
+        emit E(arr);
+    }
+}
+// ====
+// compileViaYul: also
+// ----
+// createEvent(uint256): 42 ->
+// ~ emit E(uint256[]): 0x20, 0x03, 0x2a, 0x2b, 0x2c
+// gas irOptimized: 115211
+// gas legacy: 116393
+// gas legacyOptimized: 114415