Disambiguation by add year suffix was not present - Added it to the s…

…tyle (#4200)

Thanks -- sorry that took so long to merge!

international-journal-of-spatial-data-infrastructures-research.csl

@@ -154,7 +154,7 @@
       <label form="short" prefix=" (" text-case="title" suffix=")"/>
     </names>
   </macro>
-  <citation et-al-min="3" et-al-use-first="1" disambiguate-add-names="true" disambiguate-add-givenname="true" givenname-disambiguation-rule="primary-name">
+  <citation et-al-min="3" et-al-use-first="1" disambiguate-add-names="true" disambiguate-add-givenname="true" givenname-disambiguation-rule="primary-name" disambiguate-add-year-suffix="true">
     <layout prefix="(" suffix=")" delimiter="; ">
       <text macro="contributors-short"/>
       <text macro="issued" prefix=", "/>