Use a single handler for executing all commands (#6826)

* Document current implementations of command handlers

* Add unit tests for execHAndler

* Refactor pkg/devfile/image to inject Backend as dependency

* Use same handler for kubedev/podmandev

* Fail after SelectBackend==nil only if backend is needed

* Move runHandler to dev/common

* Unit tests for runHandler

* Create a component.ExecuteTerminatingCommand

* ExecuteTerminatingCommand/ExecuteNonTerminatingCommand for Handler

* Fix calling other command types

* Consider parent group to determine if a command is terminating

* Replace component.execHandler by common.runHandler

* Remove execHandler

* Make runHandler and most of fields private and pass containersRunning to handler

* Pass containersRunning value

* deploy using common Handler

* Fix tests

* Use specific Dev/Deploy mode for Apply

* Fix cmdline for job

* Fix unit tests

* Pass appName and componentName with ctx to handler

* Move handler to pkg/component package

* Update doc

* Unit tests Deploy

* Unit tests Build

* Unit tests Run

* Unit tests PostStart

* Unit tests PreStop

* Update doc

* Fix Podman tests

* Fix hotReload on podman

* Change podman version timeout to 30s for tests

* Cleanup + fix doc

scripts/mockgen.sh

@@ -99,3 +99,7 @@ $mockgen -source=pkg/podman/interface.go \
 $mockgen -source=pkg/configAutomount/interface.go \
     -package configAutomount \
     -destination pkg/configAutomount/mock.go
+
+$mockgen -source=pkg/platform/interface.go \
+    -package platform \
+    -destination pkg/platform/mock.go