Fix issue with social buttons. (USRSE#1205)

The `site.url` variable needs to be the site domain.
The absence of a value causes URLs using `site.url` to not
contain this, which then prevents social sites from linking
to the site.

This change fixes the `site.url` variable and maintains
the circleci build behavior to maintain preview of assets.

Closes USRSE#1201

.circleci/circle_urls.sh

@@ -1,2 +1,3 @@
 BASEURL=https://output.circle-artifacts.com/output/job/${CIRCLE_WORKFLOW_JOB_ID}/artifacts/${CIRCLE_NODE_INDEX}/usrse.github.io
 sed -i "8 s,.*,baseurl: $BASEURL,g" "_config.yml"
+sed -i "7 s,.*,url: \"\",g" "_config.yml"

_config.yml

@@ -4,7 +4,7 @@ lang: en
 title: US-RSE
 description: United States Research Software Engineer Association
 
-url: ""
+url: "https://us-rse.org"
 baseurl: ""  # for testing, also check .circleci/circle_urls.sh
 title-img: /assets/img/main_logo_transparent.png  # baseurl will be prepended
 twitter-img: /assets/img/main_logo_transparent.png  # url + baseurl will be prepended