Change CHANGES

Signed-off-by: Ulysse Gérard <thevoodoos@gmail.com>

Author: voodoos

CHANGES.md

@@ -13,6 +13,9 @@ next
 - Improve error message when invalid package names (such as the empty string)
   are passed to `dune build -p`. (#3561, @emillon)
 
+- Allow the use of the `context_name` variable in the `enabled_if` fields of
+  executable(s) and install stanzas. (#3568, fixes #3566, @voodoos)
+
 2.6.0 (05/06/2020)
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