Add descriptions to IssuableStateEnum

Updated schema/docs

app/graphql/types/issuable_state_enum.rb

@@ -5,9 +5,9 @@ module Types
     graphql_name 'IssuableState'
     description 'State of a GitLab issue or merge request'
 
-    value 'opened'
-    value 'closed'
-    value 'locked'
-    value 'all'
+    value 'opened', description: "In open state"
+    value 'closed', description: "In closed state"
+    value 'locked', description: "Discussion has been locked"
+    value 'all', description: 'All available'
   end
 end

doc/api/graphql/reference/index.md

@@ -5152,10 +5152,10 @@ State of a GitLab issue or merge request.
 
 | Value | Description |
 | ----- | ----------- |
-| `all` |  |
-| `closed` |  |
-| `locked` |  |
-| `opened` |  |
+| `all` | All available |
+| `closed` | In closed state |
+| `locked` | Discussion has been locked |
+| `opened` | In open state |
 
 ### IssueSort
 
@@ -5195,10 +5195,10 @@ State of a GitLab issue.
 
 | Value | Description |
 | ----- | ----------- |
-| `all` |  |
-| `closed` |  |
-| `locked` |  |
-| `opened` |  |
+| `all` | All available |
+| `closed` | In closed state |
+| `locked` | Discussion has been locked |
+| `opened` | In open state |
 
 ### IssueStateEvent
 
@@ -5338,11 +5338,11 @@ State of a GitLab merge request.
 
 | Value | Description |
 | ----- | ----------- |
-| `all` |  |
-| `closed` |  |
-| `locked` |  |
+| `all` | All available |
+| `closed` | In closed state |
+| `locked` | Discussion has been locked |
 | `merged` | Merge Request has been merged |
-| `opened` |  |
+| `opened` | In open state |
 
 ### MilestoneStateEnum