Rename "Slash commands" to "Quick actions"

Fix https://gitlab.com/gitlab-org/gitlab-ce/issues/27070

Deprecate "chat commands" in favor of "slash commands"

We looked for things like:

 - `slash commmand`
 - `slash_command`
 - `slash-command`
 - `SlashCommand`

1 files changed, 39 insertions, 0 deletions

diff --git a/doc/user/project/quick_actions.md b/doc/user/project/quick_actions.md
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index 00000000000..19b51c83222
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+# GitLab quick actions
+
+Quick actions are textual shortcuts for common actions on issues or merge
+requests that are usually done by clicking buttons or dropdowns in GitLab's UI.
+You can enter these commands while creating a new issue or merge request, and
+in comments. Each command should be on a separate line in order to be properly
+detected and executed. The commands are removed from the issue, merge request or
+comment body before it is saved and will not be visible to anyone else.
+
+Below is a list of all of the available commands and descriptions about what they
+do.
+
+| Command                    | Action       |
+|:---------------------------|:-------------|
+| `/close`                   | Close the issue or merge request |
+| `/reopen`                  | Reopen the issue or merge request |
+| `/merge`                   | Merge (when pipeline succeeds) |
+| `/title <New title>`       | Change title |
+| `/assign @username`        | Assign |
+| `/unassign`                | Remove assignee |
+| `/milestone %milestone`    | Set milestone |
+| `/remove_milestone`        | Remove milestone |
+| `/label ~foo ~"bar baz"`   | Add label(s) |
+| `/unlabel ~foo ~"bar baz"` | Remove all or specific label(s) |
+| `/relabel ~foo ~"bar baz"` | Replace all label(s) |
+| `/todo`                    | Add a todo |
+| `/done`                    | Mark todo as done |
+| `/subscribe`               | Subscribe |
+| `/unsubscribe`             | Unsubscribe |
+| <code>/due &lt;in 2 days &#124; this Friday &#124; December 31st&gt;</code> | Set due date |
+| `/remove_due_date`         | Remove due date |
+| `/wip`                     | Toggle the Work In Progress status |
+| <code>/estimate &lt;1w 3d 2h 14m&gt;</code> | Set time estimate |
+| `/remove_estimate`       | Remove estimated time |
+| <code>/spend &lt;1h 30m &#124; -1h 5m&gt;</code> | Add or subtract spent time |
+| `/remove_time_spent`       | Remove time spent |
+| `/target_branch <Branch Name>` | Set target branch for current merge request |
+| `/award :emoji:`  | Toggle award for :emoji: |
+| `/board_move ~column`      | Move issue to column on the board |