completions/rclone: Add version parsing

This had a weird, unnecessary and terrible backwards-incompatibility
in how you get the completions out.

I do not like it but I am in a good enough mood to work around it.

See #9878.

share/completions/rclone.fish

@@ -1 +1,10 @@
-rclone completion fish - | source
+set -l rclone_version (rclone version | string match -rg 'rclone v(.*)' | string split .)
+or return
+
+# Yes, rclone's parsing here has changed, now they *require* a `-` argument
+# where previously they required *not* having it.
+if test "$rclone_version[1]" -gt 1; or test "$rclone_version[2]" -gt 62
+    rclone completion fish - 2>/dev/null | source
+else
+    rclone completion fish 2>/dev/null | source
+end