Add v1.25.10 release to CHANGES on master
Changes
=======
+1.25.10 (2020-07-22)
+--------------------
+
+* Added support for ``SSLKEYLOGFILE`` environment variable for
+ logging TLS session keys with use with programs like
+ Wireshark for decrypting captured web traffic (Pull #1867)
+
+* Fixed loading of SecureTransport libraries on macOS Big Sur
+ due to the new dynamic linker cache (Pull #1905)
+
+* Collapse chunked request bodies data and framing into one
+ call to ``send()`` to reduce the number of TCP packets by 2-4x (Pull #1906)
+
+* Don't insert ``None`` into ``ConnectionPool`` if the pool
+ was empty when requesting a connection (Pull #1866)
+
+* Avoid ``hasattr`` call in ``BrotliDecoder.decompress()`` (Pull #1858)
+
+
1.25.9 (2020-04-16)
-------------------
