docs: update fetchpost description to show what content types are s…

…upported

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README.md

@@ -45,7 +45,7 @@
 | [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), [jaq](https://github.com/01mf02/jaq?tab=readme-ov-file#jaq) JSON query language support, dynamic throttling ([RateLimit](https://www.ietf.org/archive/id/draft-ietf-httpapi-ratelimit-headers-06.html)) & caching with available persistent caching using [Redis](https://redis.io/) or a disk-cache. |
-| [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/)) |
+| [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/)). Supports both HTML form (application/x-www-form-urlencoded) and JSON (application/json) content types. |
 | [fill](/src/cmd/fill.rs#L2)<br>👆 | Fill empty values.  |
 | [fixlengths](/src/cmd/fixlengths.rs#L2) | Force a CSV to have same-length records by either padding or truncating them. |
 | [flatten](/src/cmd/flatten.rs#L2) | A flattened view of CSV records. Useful for viewing one record at a time.<br />e.g. `qsv slice -i 5 data.csv \| qsv flatten`. |