Merge #771: fix CHANGELOG.md for 0.23.0

4b00c71 global-context-less-secure enables global-context, not the other way around (eyusufatik)

Pull request description:

  The mentioned commit in the changelog is this: c1bb316

  Change looks unnecessary, however, I had a minor heart-attack once I saw the changelog because we've been using the global-context feature for some time.

ACKs for top commit:
  apoelstra:
    ACK 4b00c71; successfully ran local tests

Tree-SHA512: 68af4a4257abee5a92157d638fa4c7ac4855aba98b45c558adf7ae22edd478f9d50b39d2ab6f708f6b1963b84fd25127930b0e7dccc6eb0c32302b684b41e678

CHANGELOG.md

@@ -120,7 +120,7 @@ The major change in this version is the increase of the Minimum Supported Rust V
 
 ## Other improvements
 
-* `global-context` feature now activates `global-context-less-secure`.
+* `global-context-less-secure` feature now activates `global-context`.
 * `githooks/` directory added for contributors
 * [Clippy is now used in CI](https://github.com/rust-bitcoin/rust-secp256k1/pull/448) and the code is clippy-compliant
 * Various documentation improvements