Update changelog version 0.2.1

HISTORY.rst

@@ -2,6 +2,10 @@
 History
 =======
 
+0.2.1 (2023-07-18)
+------------------
+* Set default service uri to demo instance.
+
 0.2.0 (2023-07-18)
 ------------------
 * Improve default palette templates.

graph_exploring_tool/__init__.py

@@ -1,3 +1,3 @@
 """Graph Exploring Tool."""
-__version__ = "0.2.0"
+__version__ = "0.2.1"
 __version_info__ = tuple((int(num) if num.isdigit() else num for num in __version__.replace("-", ".", 1).split(".")))