bump minor version

DhairyaLGandhi · web-flow · commit c9d7d34b27ff · 2021-02-18T15:28:31.000+05:30
Since this changes the behaviour of saved dicts, a breaking version is better suited to propagate across the ecosystem
diff --git a/Project.toml b/Project.toml
@@ -1,6 +1,6 @@
 name = "BSON"
 uuid = "fbb218c0-5317-5bc6-957e-2ee96dd4b1f0"
-version = "0.2.7"
+version = "0.3.0"
 
 [compat]
 julia = "0.7, 1"
