Fix UriPathEncoder bug to improve performance

Fix `isAllowed` check and write test to ensure that additional object
instances are not created unnecessarily.

See gh-40615

Author: philwebb

spring-boot-project/spring-boot-tools/spring-boot-loader/src/main/java/org/springframework/boot/loader/nio/file/UriPathEncoder.java

@@ -36,7 +36,7 @@ private UriPathEncoder() {
 	static String encode(String path) {
 		byte[] bytes = path.getBytes(StandardCharsets.UTF_8);
 		for (byte b : bytes) {
-			if (isAllowed(b)) {
+			if (!isAllowed(b)) {
 				return encode(bytes);
 			}
 		}

spring-boot-project/spring-boot-tools/spring-boot-loader/src/test/java/org/springframework/boot/loader/nio/file/UriPathEncoderTests.java

@@ -34,4 +34,10 @@ void encodePath() {
 		assertThat(UriPathEncoder.encode("/Z\u00fcrich")).isEqualTo("/Z%C3%BCrich");
 	}
 
+	@Test
+	void encodePathWhenNoEncodingIsRequiredReturnsSameInstance() {
+		String path = "/foo/bar";
+		assertThat(UriPathEncoder.encode(path)).isSameAs(path);
+	}
+
 }