Description extract can also synchronize org-trello's metadata which it must not

[ardumont]

Evaluating this code works and displays "hello there\n":

(orgtrello-tests/with-temp-buffer "* TODO Joy of FUN(ctional) LANGUAGES
:PROPERTIES:
:orgtrello-id: 52c945143004d4617c012528
:orgtrello-users:
:END:
hello there
- [-] LISP family :PROPERTIES: {\"orgtrello-id\":\"52c945140a364c5226007314\"}
- [X] Emacs-Lisp :PROPERTIES: {\"orgtrello-id\":\"52c9451784251e1b260127f8\"}
- [X] Common-Lisp :PROPERTIES: {\"orgtrello-id\":\"52c94518b2c5b28e37012ba4\"}"
       (orgtrello-buffer/extract-description-from-current-position))

This does not and displays ":PROPERTIES:
 :orgtrello-id: 52c945143004d4617c012528
 :orgtrello-users:
 :END:

hello there
".
This is due to the blanks before org-trello's metadata properties.

``` emacs-lisp
(orgtrello-tests/with-temp-buffer "* TODO Joy of FUN(ctional) LANGUAGES
  :PROPERTIES:
 :orgtrello-id: 52c945143004d4617c012528
 :orgtrello-users:
 :END:
hello there
- [-] LISP family :PROPERTIES: {\"orgtrello-id\":\"52c945140a364c5226007314\"}
- [X] Emacs-Lisp :PROPERTIES: {\"orgtrello-id\":\"52c9451784251e1b260127f8\"}
- [X] Common-Lisp :PROPERTIES: {\"orgtrello-id\":\"52c94518b2c5b28e37012ba4\"}"
       (orgtrello-buffer/extract-description-from-current-position))

To fix.