[Nearby Share] Update NS Settings string

Updates the settings strings to shown in the Connected devices
settings page when NS is off or disabled. The new strings provide
a link for users to learn more about NS in both cases. When
NS is off, instead of saying 'Off', now the page gives a description
of NS

The new strings to be used are those used regardless of whether
os-settings-revamp-wayfinding
was enabled: before, there were different strings used if enabled.

For this reason, the code conditioning the strings shown on
the flag state are removed.

Before
--------------------------------------------
Revamp Wayfinding: Disabled
---------------------------
NS: Disabled
https://screenshot.googleplex.com/9h3h4asJdppdQyN.png

NS: On
https://screenshot.googleplex.com/A7hPyFKheYEXJGC.png

NS: Off
https://screenshot.googleplex.com/7H5j9DMHtF4ukKR.png

Revamp Wayfinding: Enabled
--------------------------
NS: Disabled
https://screenshot.googleplex.com/AxvUQjCn3gRGbvx.png

NS: On
https://screenshot.googleplex.com/7RJ839YD9qHYEUB.png

NS: Off
https://screenshot.googleplex.com/8hFo8wfnLYBo2QP.png


After
--------------------------------------------
Revamp Wayfinding: Disabled
---------------------------
NS: Disabled
https://screenshot.googleplex.com/7sBPs2sYXG6cAgJ.png

NS: On
https://screenshot.googleplex.com/AVMHa5wB5SQQWJS.png

NS: Off
https://screenshot.googleplex.com/8UhLxpgxP8nbYwg.png

Revamp Wayfinding: Enabled
--------------------------
NS: Disabled
https://screenshot.googleplex.com/GcYddhTztfiUKFT.png

NS: On
https://screenshot.googleplex.com/BYfthDJBHaJ6Zru.png

NS: Off
https://screenshot.googleplex.com/32km8jNyMfkAiP2.png

        Visibility strings for all visibilities when NS is enabled
        appear as expected; because none were changed, screenshots
        above of NS enabled and on show a device set to 'All contacts'
        visibility.

Tested: all unit tests in browser_tests pass.
Fixed: b/316389476
Change-Id: Iaa05067078e1e85d7ff5102a80949d1d6b9f1279
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5208313
Reviewed-by: Jon Mann <jonmann@chromium.org>
Commit-Queue: Brando Socarras <brandosocarras@google.com>
Reviewed-by: Ken Rockot <rockot@google.com>
Cr-Commit-Position: refs/heads/main@{#1250570}