Reformat institution rule page

docs/CMIP6Plus/Rules/institution.md

@@ -28,6 +28,6 @@ This is the full name of the institution. This should match >90% with one of the
 <img src='https://raw.githubusercontent.com/ror-community/ror-logos/main/ror-icon-rgb.svg' style='height:3em'/>
 [Research Organisation Repository](ror.org) is a global, community-led registry of open persistent identifiers for research organizations. This gives us an ability to assign a unique identifier to each institution, which persists even after they have rebranded, merged, split, shut down, and re-emerged. 
 
-*Rules* : <b> An alphanumeric string of 9 characters as defined by ROR.org entry. </b>
+*Rules* : <b> An alphanumeric string, 9 characters, defined by ROR.org </b>