trpc-proto-http: fix response header parsing in HttpConsumerInvoker (#135)

* trpc-proto-http: fix response header parsing in HttpConsumerInvoker

The previous implementation iterated over HeaderElement objects and
called element.getName() to extract header values. This only returns
the token before the first '=' or ';' delimiter, causing truncation
of composite header values such as:

  Content-Type: application/json; charset=utf-8  ->  "application/json"
  X-Token: key=abc123                            ->  "key"
  Set-Cookie: sessionId=abc; Path=/; HttpOnly    ->  "sessionId"

Fix this by calling header.getValue() directly to obtain the complete
header value, consistent with the approach already used in
Http2ConsumerInvoker. Also remove the now-unused HeaderElement import.

Add HttpConsumerInvokerTest covering:
- simple header values (no delimiters)
- composite values containing semicolons (core fix scenario)
- values containing equals signs
- multiple headers all stored correctly
- header values stored as byte[] (tRPC protocol consistency)
- non-200 status code throws TRpcException
- zero Content-Length returns empty response body
- complex cookie header with multiple semicolons and equals signs
- non-zero Content-Length with response body decoded correctly

* trpc-proto-http: fix comment

Author: PingruiLi

trpc-proto/trpc-proto-http/src/main/java/com/tencent/trpc/proto/http/client/HttpConsumerInvoker.java

@@ -32,7 +32,6 @@
 import java.util.Objects;
 import org.apache.commons.io.IOUtils;
 import org.apache.http.Header;
-import org.apache.http.HeaderElement;
 import org.apache.http.HttpHeaders;
 import org.apache.http.HttpRequest;
 import org.apache.http.HttpStatus;
@@ -93,10 +92,8 @@ private Response handleResponse(Request request, CloseableHttpResponse httpRespo
         Map<String, Object> respAttachments = new HashMap<>();
         for (Header header : httpResponse.getAllHeaders()) {
             String name = header.getName();
-            for (HeaderElement element : header.getElements()) {
-                String value = element.getName();
-                respAttachments.put(name, value.getBytes(StandardCharsets.UTF_8));
-            }
+            String value = header.getValue();
+            respAttachments.put(name, value.getBytes(StandardCharsets.UTF_8));
         }
 
         Header contentLengthHdr = httpResponse.getFirstHeader(HttpHeaders.CONTENT_LENGTH);