Revert "pw_containers: Warn about unsafe Vector usage"

This reverts commit 44287c6.

Reason for revert: b/313899658 is marked as Fixed.

Original change's description:
> pw_containers: Warn about unsafe Vector usage
>
> Bug: b/313899658
> Change-Id: I59694ca28e807e1fc277746cb0930f599becda7b
> Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/182970
> Presubmit-Verified: CQ Bot Account <[email protected]>
> Commit-Queue: Ted Pudlik <[email protected]>
> Reviewed-by: Aaron Green <[email protected]>

Bug: b/313899658
Change-Id: I1fc0e890790a366994453a63a418c82d397705ac
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/232651
Commit-Queue: Jonathon Reinhart <[email protected]>
Reviewed-by: Ted Pudlik <[email protected]>
Reviewed-by: Jonathon Reinhart <[email protected]>
Lint: Lint 🤖 <[email protected]>

pw_containers/docs.rst

@@ -19,12 +19,6 @@ size in a variable. This allows Vectors to be used without having to know
 their maximum size at compile time. It also keeps code size small since
 function implementations are shared for all maximum sizes.
 
-.. admonition:: Non-trivially-destructible, self-referencing types
-
-   ``pw::Vector`` is not safe to use with non-trivially-destructible,
-   self-referencing types. See `b/313899658
-   <https://issues.pigweed.dev/issues/313899658>`_.
-
 ---------------
 pw::InlineDeque
 ---------------