chore: Add copyright and license headers (#23)

* chore: Add copyright and license headers

This commit adds the Apache 2.0 license and a copyright notice to the header of all source files. This ensures that the licensing and copyright information is clearly stated within the codebase.

* cargo fmt

* fix

* fmt

* fix clippy

crates/obs/src/sinks/webhook.rs

@@ -1,3 +1,17 @@
+// Copyright 2024 RustFS Team
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
 use crate::UnifiedLogEntry;
 use crate::sinks::Sink;
 use async_trait::async_trait;
@@ -57,7 +71,7 @@ impl Sink for WebhookSink {
             }
         }
 
-        eprintln!("Failed to send log to webhook after {} retries", self.max_retries);
+        eprintln!("Failed to send log to webhook after {0} retries", self.max_retries);
     }
 }
 
@@ -65,6 +79,6 @@ impl Drop for WebhookSink {
     fn drop(&mut self) {
         // Perform any necessary cleanup here
         // For example, you might want to log that the sink is being dropped
-        eprintln!("Dropping WebhookSink with URL: {}", self.endpoint);
+        eprintln!("Dropping WebhookSink with URL: {0}", self.endpoint);
     }
 }