[chore][receiver/syslog] Remove inaccurate field from doc (open-telem…

…etry#27883)

Resolves open-telemetry#27871

receiver/syslogreceiver/README.md

@@ -27,8 +27,6 @@ Parses Syslogs received over TCP or UDP.
 | `location` | `UTC` | The geographic location (timezone) to use when parsing the timestamp (Syslog RFC 3164 only). The available locations depend on the local IANA Time Zone database. [This page](https://en.wikipedia.org/wiki/List_of_tz_database_time_zones) contains many examples, such as `America/New_York`. |
 | `enable_octet_counting` | `false` | Wether or not to enable [RFC 6587](https://www.rfc-editor.org/rfc/rfc6587#section-3.4.1) Octet Counting on syslog parsing (Syslog RFC 5424 and TCP only). |
 | `non_transparent_framing_trailer` | `nil` | The framing trailer, either `LF` or `NUL`, when using [RFC 6587](https://www.rfc-editor.org/rfc/rfc6587#section-3.4.2) Non-Transparent-Framing (Syslog RFC 5424 and TCP only). |
-| `timestamp` | `nil` | An optional [timestamp](../../pkg/stanza/docs/types/timestamp.md) block which will parse a timestamp field before passing the entry to the output operator |
-| `severity` | `nil` | An optional [severity](../../pkg/stanza/docs/types/severity.md) block which will parse a severity field before passing the entry to the output operator |
 | `attributes` | {} | A map of `key: value` labels to add to the entry's attributes |
 | `resource` | {} | A map of `key: value` labels to add to the entry's resource |
 | `operators` | [] | An array of [operators](../../pkg/stanza/docs/operators/README.md#what-operators-are-available). See below for more details |