[NFC] fix up typo in v6.40 release notes

(cherry picked from commit 0f9a021)

Author: jblomer

README/ReleaseNotes/v640/index.md

@@ -222,7 +222,7 @@ This should be used for multi-stream reading where multiple threads share a sing
 
 ### HTTP I/O
 
-- There is a new HTTP I/O implementation in ROOT based on libcurl. It provides modern HTTP remote read capabilities (HTTP/2, compression, secure transport, etc.) on Linux, macOS, and Windows. The new HTTP I/O can also connect to protected resources on S3 enpoints using the `S3_ACCCESS_KEY`, `S3_SECRET_KEY`, and `S3_REGION` environment variables. By default, the new HTTP I/O is automaticlly built if libcurl is found on the system (manual cmake option: `-Dcurl=[on|off]`). If both, Davix based and libcurl based HTTP plugins are available, the Davix plugin has precedence unless `Curl.ReplaceDavix: yes` is set in the `root.rc`.
+- There is a new HTTP I/O implementation in ROOT based on libcurl. It provides modern HTTP remote read capabilities (HTTP/2, compression, secure transport, etc.) on Linux, macOS, and Windows. The new HTTP I/O can also connect to protected resources on S3 enpoints using the `S3_ACCCESS_KEY`, `S3_SECRET_KEY`, and `S3_REGION` environment variables. By default, the new HTTP I/O is automaticlly built if libcurl is found on the system (manual cmake option: `-Dcurl=[on|off]`). If both, Davix based and libcurl based HTTP plugins are available, the Davix plugin has precedence unless `Curl.ReplaceDavix: yes` is set in the `.rootrc`.
 
 ## Math