fix: graal error for private @Property

Changes to inject @Property(name = "logger.config") via constructor injection.

Graal 22.3 and Micronaut 3.8.0 was throwing:

```
Caused by: java.lang.NoSuchFieldError: No field 'logbackXmlLocation' found for type: io.micronaut.management.endpoint.loggers.impl.LogbackLoggingSystem
195	at io.micronaut.core.reflect.ReflectionUtils.lambda$getRequiredField$2(ReflectionUtils.java:294)
196	at java.base@17.0.5/java.util.Optional.orElseThrow(Optional.java:403)
197	at io.micronaut.core.reflect.ReflectionUtils.getRequiredField(ReflectionUtils.java:294)
198	at io.micronaut.context.AbstractInitializableBeanDefinition.setFieldWithReflection(AbstractInitializableBeanDefinition.java:979)
199	... 113 common frames omitted
```

management/src/main/java/io/micronaut/management/endpoint/loggers/impl/LogbackLoggingSystem.java

@@ -24,6 +24,7 @@
 import io.micronaut.context.annotation.Replaces;
 import io.micronaut.context.annotation.Requires;
 import io.micronaut.core.annotation.NonNull;
+import io.micronaut.core.annotation.Nullable;
 import io.micronaut.logging.LogLevel;
 import io.micronaut.logging.LoggingSystemException;
 import io.micronaut.management.endpoint.loggers.LoggerConfiguration;
@@ -35,7 +36,6 @@
 import java.net.URL;
 import java.util.Collection;
 import java.util.Objects;
-import java.util.Optional;
 import java.util.stream.Collectors;
 
 /**
@@ -51,8 +51,11 @@
 public class LogbackLoggingSystem implements ManagedLoggingSystem, io.micronaut.logging.LoggingSystem {
     private static final String DEFAULT_LOGBACK_LOCATION = "logback.xml";
 
-    @Property(name = "logger.config")
-    private Optional<String> logbackXmlLocation;
+    private final String logbackXmlLocation;
+
+    public LogbackLoggingSystem(@Nullable @Property(name = "logger.config") String logbackXmlLocation) {
+        this.logbackXmlLocation = logbackXmlLocation != null ? logbackXmlLocation : DEFAULT_LOGBACK_LOCATION;
+    }
 
     @Override
     @NonNull
@@ -117,18 +120,17 @@ private static Level toLevel(LogLevel logLevel) {
             return Level.valueOf(logLevel.name());
         }
     }
-    
+
     @Override
     public void refresh() {
         LoggerContext context = getLoggerContext();
         context.reset();
-        String logbackXml = logbackXmlLocation.orElse(DEFAULT_LOGBACK_LOCATION);
-        URL resource = getClass().getClassLoader().getResource(logbackXml);
+        URL resource = getClass().getClassLoader().getResource(logbackXmlLocation);
         if (Objects.isNull(resource)) {
-            throw new LoggingSystemException("Resource " + logbackXml + " not found");
+            throw new LoggingSystemException("Resource " + logbackXmlLocation + " not found");
         }
 
-        try {            
+        try {
             new ContextInitializer(context).configureByResource(resource);
         } catch (JoranException e) {
             throw new LoggingSystemException("Error while refreshing Logback", e);

runtime/src/main/java/io/micronaut/logging/impl/LogbackLoggingSystem.java

@@ -45,7 +45,7 @@ public final class LogbackLoggingSystem implements LoggingSystem {
 
     private static final String DEFAULT_LOGBACK_LOCATION = "logback.xml";
 
-    private String logbackXmlLocation;
+    private final String logbackXmlLocation;
 
     public LogbackLoggingSystem(@Nullable @Property(name = "logger.config") String logbackXmlLocation) {
         this.logbackXmlLocation = logbackXmlLocation != null ? logbackXmlLocation : DEFAULT_LOGBACK_LOCATION;