api: deprecate webxdc descr parameter (#6255)

this PR removes most usages of the `descr` parameter.

- to avoid noise in different branches etc. (as annoying on similar, at
a first glance simple changes), i left the external API stable

- also, the effort to do a database migration seems to be over the top,
so the column is left and set to empty strings on future updates - maybe
we can recycle the column at some point ;)

closes #6245

deltachat-ffi/src/lib.rs

@@ -1065,7 +1065,7 @@ pub unsafe extern "C" fn dc_send_webxdc_status_update(
     context: *mut dc_context_t,
     msg_id: u32,
     json: *const libc::c_char,
-    descr: *const libc::c_char,
+    _descr: *const libc::c_char,
 ) -> libc::c_int {
     if context.is_null() {
         eprintln!("ignoring careless call to dc_send_webxdc_status_update()");
@@ -1073,14 +1073,10 @@ pub unsafe extern "C" fn dc_send_webxdc_status_update(
     }
     let ctx = &*context;
 
-    block_on(ctx.send_webxdc_status_update(
-        MsgId::new(msg_id),
-        &to_string_lossy(json),
-        &to_string_lossy(descr),
-    ))
-    .context("Failed to send webxdc update")
-    .log_err(ctx)
-    .is_ok() as libc::c_int
+    block_on(ctx.send_webxdc_status_update(MsgId::new(msg_id), &to_string_lossy(json)))
+        .context("Failed to send webxdc update")
+        .log_err(ctx)
+        .is_ok() as libc::c_int
 }
 
 #[no_mangle]