[Sol->Yul] Implementing Byte array push() and pop()

test/libsolidity/semanticTests/array/byte_array_transitional_2.sol

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+// Tests transition between short and long encoding both ways
+contract c {
+    bytes data;
+
+    function test() public returns (uint256) {
+        for (uint8 i = 0; i < 33; i++) {
+            data.push(bytes1(i));
+        }
+        for (uint8 i = 0; i < data.length; i++)
+            if (data[i] != bytes1(i)) return i;
+        data.pop();
+        data.pop();
+        for (uint8 i = 0; i < data.length; i++)
+            if (data[i] != bytes1(i)) return i;
+        return 0;
+    }
+}
+// ====
+// compileViaYul: also
+// ----
+// test() -> 0