PYTHON-4376 Fix typo in changelog (#1611)

Author: blink1073

doc/changelog.rst

@@ -48,7 +48,7 @@ PyMongo 4.7 brings a number of improvements including:
 
 .. warning:: PyMongo depends on ``dnspython``, which released version 2.6.1 with a fix for
    `CVE-2023-29483 <https://www.cve.org/CVERecord?id=CVE-2023-29483>`_.  We do not explicitly require
-   that version, but we strongly recommend that you install at last that version in your environment.
+   that version, but we strongly recommend that you install at least that version in your environment.
 
 Unavoidable breaking changes
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