Exempt: Trivial - WDFN-697 try replace filter to encode slash

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Description WDFN-697 try replace filter to encode slash

It looks like the Jinja2 filter 'urlencode' will not encode slashes '/' which seems to mess up the Twitter share. The documentation suggests using the 'replace' filter to encode the slashes, so giving that a try. Also trying to explicitly set the image size for Facebook as the documentation indicates that if the size is not set, it will not show the image in the post until Facebook 'processes' the image.

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