[chore] Update CONTRIBUTING.md (#21534)

The wrong label "needs discussion" is replaced with "discussion needed"

CONTRIBUTING.md

@@ -270,7 +270,7 @@ triaged and is ready for work. If someone who is assigned to an issue is no long
 | `flaky test` | A test unexpectedly failed during CI, showing that there is a problem with the tests or test setup that is causing the tests to intermittently fail. |
 | `good first issue` | Implementing this issue would not require specialized or in-depth knowledge about the component and is ideal for a new or first-time contributor to take. |
 | `help wanted` | The code owners for this component do not expect to have time to work on it soon, and would welcome help from contributors. |
-| `needs discussion`  | This issue needs more input from the maintainers or community before work can be started. |
+| `discussion needed` | This issue needs more input from the maintainers or community before work can be started. |
 | `needs triage` | This label is added automatically, and can be removed when a triager or code owner deems that an issue is either ready for work or should not need any work. |
 | `waiting for author` | Can be applied when input is required from the author before the issue can move any further. |
 | `priority:p0` | A critical security vulnerability or Collector panic using a default or common configuration unrelated to a specific component. |
@@ -292,7 +292,7 @@ The following general labels are supported:
 |----------------------|----------------------|
 | `good first issue` | `good-first-issue` |
 | `help wanted` | `help-wanted` |
-| `needs discussion`  | `needs-discussion`  |
+| `discussion needed` | `discussion-needed` |
 | `needs triage` | `needs-triage` |
 | `waiting for author` | `waiting-for-author` |