Update _index.md

added a CC BY license

content/_index.md

@@ -70,5 +70,7 @@ DHCC Information, Measurement and Practice Action Group. (2022). A Researcher Gu
 See also [Grant Writing]({{< relref path="./toolkit/grant-writing.md" >}}).
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+<p xmlns:cc="http://creativecommons.org/ns#" >This work is licensed under <a href="https://creativecommons.org/licenses/by/4.0/?ref=chooser-v1" target="_blank" rel="license noopener noreferrer" style="display:inline-block;">CC BY 4.0<img style="height:22px!important;margin-left:3px;vertical-align:text-bottom;" src="https://mirrors.creativecommons.org/presskit/icons/cc.svg?ref=chooser-v1" alt=""><img style="height:22px!important;margin-left:3px;vertical-align:text-bottom;" src="https://mirrors.creativecommons.org/presskit/icons/by.svg?ref=chooser-v1" alt=""></a></p>
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