docs: fix typo "adpot" => "adopt" (#1432)

Author: robinlahtinen

packages/lit-dev-content/site/docs/v3/data/signals.md

@@ -98,7 +98,7 @@ Lit provides the
 to integrate with the official polyfill for this proposal.
 
 This proposal is very exciting for the web components ecosystem. Because all
-libraries and frameworks that adpot the standard will produce compatible signals,
+libraries and frameworks that adopt the standard will produce compatible signals,
 different web components won't have to use the same library to interoperably
 consume and produce signals.