update ratelimit link

[skip ci]

README.md

@@ -40,7 +40,7 @@ See [FAQ](https://github.com/jqnatividad/qsv/discussions/categories/faq) for mor
 | [explode](/src/cmd/explode.rs#L2) | Explode rows into multiple ones by splitting a column value based on the given separator.  |
 | [extdedup](/src/cmd/extdedup.rs#L2)<br> | Remove duplicate rows from an arbitrarily large CSV/text file using a memory-mapped, [on-disk hash table](https://crates.io/crates/odht). Unlike the `dedup` command, this command does not load the entire file into memory nor does it sort the deduped file. |
 | [extsort](/src/cmd/extsort.rs#L2)<br>🚀 | Sort an arbitrarily large CSV/text file using a multithreaded [external merge sort](https://en.wikipedia.org/wiki/External_sorting) algorithm. |
-| [fetch](/src/cmd/fetch.rs#L3)<br>✨🧠🌐 | Fetches data from web services for every row using **HTTP Get**. Comes with [HTTP/2](https://http2-explained.haxx.se/en/part1) [adaptive flow control](https://medium.com/coderscorner/http-2-flow-control-77e54f7fd518), [jql](https://github.com/yamafaktory/jql#%EF%B8%8F-usage) JSON query language support, dynamic throttling ([RateLimit](https://tools.ietf.org/id/draft-polli-ratelimit-headers-00.html)) & caching with optional [Redis](https://redis.io/) support for persistent caching. |
+| [fetch](/src/cmd/fetch.rs#L3)<br>✨🧠🌐 | Fetches data from web services for every row using **HTTP Get**. Comes with [HTTP/2](https://http2-explained.haxx.se/en/part1) [adaptive flow control](https://medium.com/coderscorner/http-2-flow-control-77e54f7fd518), [jql](https://github.com/yamafaktory/jql#%EF%B8%8F-usage) JSON query language support, dynamic throttling ([RateLimit](https://www.ietf.org/archive/id/draft-ietf-httpapi-ratelimit-headers-06.html)) & caching with optional [Redis](https://redis.io/) support for persistent caching. |
 | [fetchpost](/src/cmd/fetchpost.rs#L3)<br>✨🧠🌐 | Similar to `fetch`, but uses **HTTP Post**. ([HTTP GET vs POST methods](https://www.geeksforgeeks.org/difference-between-http-get-and-post-methods/)) |
 | [fill](/src/cmd/fill.rs#L2) | Fill empty values.  |
 | [fixlengths](/src/cmd/fixlengths.rs#L2) | Force a CSV to have same-length records by either padding or truncating them. |