src: fix dynamically linked zlib version

Report the version of the dynamically linked zlib if built with
`configure --shared-zlib` instead of the hardcoded version that
corresponds to the bundled version of zlib in `deps`.

PR-URL: https://github.com/nodejs/node/pull/51007
Refs: https://github.com/nodejs/node/pull/50910
Refs: https://github.com/nodejs/node/pull/50158
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Michael Dawson <midawson@redhat.com>

node.gypi

@@ -141,6 +141,7 @@
     } ],
     [ 'node_shared_zlib=="false"', {
       'dependencies': [ 'deps/zlib/zlib.gyp:zlib' ],
+      'defines': [ 'NODE_BUNDLED_ZLIB' ],
       'conditions': [
         [ 'force_load=="true"', {
           'xcode_settings': {

src/node_metadata.cc

@@ -15,7 +15,12 @@
 #include "uv.h"
 #include "uvwasi.h"
 #include "v8.h"
+
+#ifdef NODE_BUNDLED_ZLIB
 #include "zlib_version.h"
+#else
+#include <zlib.h>
+#endif  // NODE_BUNDLED_ZLIB
 
 #if HAVE_OPENSSL
 #include <openssl/opensslv.h>
@@ -79,7 +84,11 @@ Metadata::Versions::Versions() {
   node = NODE_VERSION_STRING;
   v8 = v8::V8::GetVersion();
   uv = uv_version_string();
+#ifdef NODE_BUNDLED_ZLIB
   zlib = ZLIB_VERSION;
+#else
+  zlib = zlibVersion();
+#endif  // NODE_BUNDLED_ZLIB
   ares = ARES_VERSION_STR;
   modules = NODE_STRINGIFY(NODE_MODULE_VERSION);
   nghttp2 = NGHTTP2_VERSION;