Add release notes for 2.0

spec/src/main/asciidoc/release_notes.asciidoc

@@ -18,6 +18,16 @@
 // Contributors:
 // Jean-Francois James, Phillip Krüger, Andy McCright, Jean-Baptiste Roux, Bojan Tomic, Adam Anderson
 
+[[release_notes_20]]
+== Release Notes for MicroProfile GraphQL 2.0
+
+A full list of changes delivered in the 2.0 release can be found at link:https://github.com/eclipse/microprofile-graphql/milestone/10[MicroProfile GraphQL 2.0 Milestone].
+
+==== Incompatible Changes
+This release aligns with Jakarta EE 9.1 (link:https://github.com/eclipse/microprofile-graphql/issues/386[386]), so it won't work with earlier versions of Jakarta or Java EE.
+
+==== API/SPI Changes
+There are no functional changes introduced in this release, except the dependency updating from javax to jakarta.
 
 [[release_notes_10]]
 == Release Notes for MicroProfile GraphQL 1.0