Do not use \b, \v and \f escapes in string literals in generated Yul code

test/libsolidity/semanticTests/literals/hex_string_with_non_printable_characters.sol

@@ -0,0 +1,12 @@
+contract C {
+    function f() public pure returns (bytes32 result) {
+        assembly {
+            result := hex"000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f"
+        }
+    }
+}
+// ====
+// compileToEwasm: also
+// compileViaYul: also
+// ----
+// f() -> 0x000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f