docs: update dnshomede API documentation (#1871)

Co-authored-by: Bodenhaltung <[email protected]>

providers/dns/dnshomede/internal/readme.md

@@ -16,22 +16,25 @@ Always returns StatusOK (200)
 
 If the API call works the first word of the response body is `successfully`.
 
-Can be a POST or a GET, the HTTP method doesn't seem to have an impact.
+If an error encoured the response body is `error - <ERRMSG>`.
+
+Can be a POST or a GET.
 
 ## Remove TXT record
 
 ```
-https://<subdomain>:<subdomain_password>@www.dnshome.de/dyndns.php?acme=rm&txt=<txtvalue>
+https://<subdomain>:<subdomain_password>@www.dnshome.de/dyndns.php?acme=rm
 ```
 
 - `<subdomain>`: the subdomain (ex: `lego.dnshome.de`).
 - `<subdomain_password>`: the subdomain password.
-- `<txtvalue>`: the value of the TXT record (12 characters minimum) (IGNORED)
 
 Only one TXT record can be used for a subdomain.
 
 Always returns StatusOK (200)
 
 If the API call works the first word of the response body is `successfully`.
 
-Can be a POST or a GET, the HTTP method doesn't seem to have an impact.
+If an error encoured the response body is `error - <ERRMSG>`.
+
+Can be a POST or a GET.