archiver: resize compressed data to actual size

archiver::compress used to rely on compressBound, but the actual
compressed size might be smaller, leading to larger output (with
trailing zeroes).

Change-Id: Ic33614f2d6bc648e59a76dec7275e71466ecaff1
Tuleap: #888

src/archiver.cpp

@@ -224,6 +224,7 @@ Archiver::compress(const std::string& str, int compressionlevel)
     auto destSize = compressBound(str.size());
     std::vector<uint8_t> outbuffer(destSize);
     int ret = ::compress(reinterpret_cast<Bytef*>(outbuffer.data()), &destSize, (Bytef*)str.data(), str.size());
+    outbuffer.resize(destSize);
 
     if (ret != Z_OK) {
         std::ostringstream oss;