minor #19170 [HttpClient] Symfony HTTP Client documentation (stipic)

This PR was squashed before being merged into the 6.3 branch.

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[HttpClient] Symfony HTTP Client documentation

notice about passing accept-encoding variable manually

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b4b65d7 [HttpClient] Symfony HTTP Client documentation

Author: javiereguiluz

http_client.rst

@@ -1049,7 +1049,11 @@ If the server does respond with a gzipped response, it's decoded transparently.
 To disable HTTP compression, send an ``Accept-Encoding: identity`` HTTP header.
 
 Chunked transfer encoding is enabled automatically if both your PHP runtime and
-the remote server supports it.
+the remote server support it.
+
+.. caution::
+
+    If you set `Accept-Encoding` to e.g. `gzip`, you will need to handle the decompression yourself.
 
 HTTP/2 Support
 ~~~~~~~~~~~~~~