Change the annotation of M3TracingHttpInterceptor.INSTANCE from @JvmStatic to @JvmField

Author: sekikatsu36

jvm/apache-httpclient/README.md

@@ -8,16 +8,16 @@ Add `M3TracingHttpInterceptor` as request/response interceptor of HttpClient.
 
 ```java:
 // CAUTION: Must setup as BOTH interceptor otherwise it may cause memory leak.
-httpclient.addRequestInterceptor(M3TracingHttpInterceptor.getINSTANCE());
-httpclient.addResponseInterceptor(M3TracingHttpInterceptor.getINSTANCE());
+httpclient.addRequestInterceptor(M3TracingHttpInterceptor.INSTANCE);
+httpclient.addResponseInterceptor(M3TracingHttpInterceptor.INSTANCE);
 ```
 
 ### httpclient 4.3+
 
 ```java
 CloseableHttpClient httpClient = HttpClientBuilder.create()
-    .addInterceptorFirst((HttpRequestInterceptor) M3TracingHttpInterceptor.getINSTANCE())
-    .addInterceptorLast((HttpResponseInterceptor) M3TracingHttpInterceptor.getINSTANCE())
+    .addInterceptorFirst((HttpRequestInterceptor) M3TracingHttpInterceptor.INSTANCE)
+    .addInterceptorLast((HttpResponseInterceptor) M3TracingHttpInterceptor.INSTANCE)
     .build();
 ```
                 }

jvm/apache-httpclient/src/main/kotlin/com/m3/tracing/apache/httpclient/M3TracingHttpInterceptor.kt

@@ -19,7 +19,7 @@ open class M3TracingHttpInterceptor(
         protected val tracer: M3Tracer
 ) : HttpRequestInterceptor, HttpResponseInterceptor {
     companion object {
-        @JvmStatic
+        @JvmField
         public val INSTANCE = M3TracingHttpInterceptor()
 
         private val currentSpan = ThreadLocal<TraceSpan>()