fix: RSA key cannot be saved normally in the Windows environment (#3510)

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#### What type of PR is this?
/kind bug
/area core
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#### What this PR does / why we need it:
修复Windows下开发环境不能正常保存Rsa密钥
#### Which issue(s) this PR fixes:

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Fixes https://github.com/halo-dev/halo/issues/3497

#### Special notes for your reviewer:
windows不支持posix标准，也无法精细控制用户访问权限，因此在不支持posix的系统直接不设置权限。
https://stackoverflow.com/questions/21541455/how-to-check-if-the-os-is-posix-compliant
#### Does this PR introduce a user-facing change?

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None
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src/main/java/run/halo/app/security/authentication/login/impl/RsaKeyService.java

@@ -6,6 +6,7 @@ import static java.nio.file.attribute.PosixFilePermission.OWNER_WRITE;
 
 import java.io.IOException;
 import java.nio.ByteBuffer;
+import java.nio.file.FileSystems;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.attribute.PosixFilePermissions;
@@ -123,8 +124,12 @@ public class RsaKeyService implements CryptoService {
             return Mono.fromRunnable(() -> {
                 try {
                     Files.createDirectories(path.getParent());
-                    Files.createFile(path,
-                        PosixFilePermissions.asFileAttribute(Set.of(OWNER_READ, OWNER_WRITE)));
+                    if (FileSystems.getDefault().supportedFileAttributeViews().contains("posix")) {
+                        Files.createFile(path,
+                            PosixFilePermissions.asFileAttribute(Set.of(OWNER_READ, OWNER_WRITE)));
+                    } else {
+                        Files.createFile(path);
+                    }
                 } catch (IOException e) {
                     // ignore the error
                     log.warn("Failed to create file for {}", path, e);