Fix: share button sometimes not working after first share

[cimigree]

closes #834

Description

• I came across this when developing Audio
• The urls for the attachments only work once for converting into readable files.
• So, in the Share button, after the first Share was pressed, the network call for converting the url to a base64 image was failing and no amount of time waiting would fix that.
• This PR uses the getUrl query to fetch a new url for each attachment every time the share button is pressed because the hook can't be used in regular functions or conditionally.
• We can't set the base64 in state because technically opening the share menu is putting the app in the background and state would clear out when share is pressed (something else I came across in the Audio development)
• This is working well, so hoping it works for you too!
• I also added failOnCancel: false so there is no error thrown if a user decides not to share the observation

To test

1. Create an observation or observations with attachments and some without
2. Share them as many times as you want without leaving the observation screen.
3. I can't test on What's App so please test on What's App for me