add breaking changes in odo 2.2 doc

docs/public/breaking-changes-in-odo-2.2.adoc

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+== Breaking changes in odo 2.2
+
+This document outlines the breaking changes that were introduced in odo 2.2.
+With the increased adoptation of https://devfile.github.io/[Devfiles] we have started to reduce odo's dependency on S2I[Source-to-Image]. Now if you dont know what that is then this document is not as relevant for you.
+
+As part of that effort the primary change that has happened is 
+
+* *`odo create --s2i <component-type>` would create a converted Devfile based component on the S2I images of that component type.*
+
+[source,sh]
+----
+odo create --s2i nodejs
+----
+
+Output - 
+
+[source,sh]
+----
+odo create nodejs --s2i
+Validation
+ ✓  Validating component [424ms]
+Conversion
+ ✓  Successfully generated devfile.yaml and env.yaml for provided S2I component
+
+Please use `odo push` command to create the component with source deployed
+----
+
+would generate a `devfile.yaml` which would be using the S2I images and variables that are part of the `nodejs`.
+
+* *Currently devfile components do not support `--git` and `--binary` components hence we still use S2I component flow when a user wants to create them.*
+
+[source,sh]
+----
+odo create java --s2i --git ./build.war
+Validation
+ ✓  Validating component [431ms]
+
+Please use `odo push` command to create the component with source deployed
+----
+Note - observe there wasn't any conversion step involved here.
+
+* *`odo env set DebugPort` wont work with converted devfile components, instead you would need to use `odo config set --env DEBUG_PORT`.*
+
+. Currently the `wildfly` and `dotnet` component types are not working when converted. We have an issue open for this - https://github.com/openshift/odo/issues/4623 
+
+=== Known bugs and limitations
+
+* https://github.com/openshift/odo/issues/4623
+* https://github.com/openshift/odo/issues/4615
+* https://github.com/openshift/odo/issues/4594
+* https://github.com/openshift/odo/issues/4593
+
+
+=== Frequently asked questions
+
+* Why odo create URL would fail as it is allowed for devfile ?
+
+It won’t fail in the sense that if you tried the conventional s2i approach and try to create odo url create it would fail with url for 8080 port already present as there would already be one for you. issue - #4621
+
+* Not sure to understand the status of the debug
+
+odo env set DebugPort wont work, instead you would need to use odo config set --env DEBUG_PORT - this is because the s2i to devfile converted devfiles dont have a debug type command defined in them. We would fix this too.
+
+* So every component will now be reported as devfile component but what about existing S2I components
+
+They should work as is mostly because I tried them and they work, maybe try odo list because that one is quite complex to work across the board.
+
+* If oc based checks in tests are not going to work, is there an alternative odo support around it ?
+
+I wouldn't say you cannot use oc based checks but they would break because now s2i components being converted to devfile would generate a deployment but the oc would try to find a DeploymentConfig.