Update bash command results to use dark-on-light-grey theme

Changed the styling for bash command results in sketch-tool-card.ts from
a light-on-dark theme to a dark-on-light-grey theme to be consistent with
other parts of the UI.

Co-Authored-By: sketch
diff --git a/loop/webui/src/web-components/sketch-tool-card.ts b/loop/webui/src/web-components/sketch-tool-card.ts
index 39fadf8..8e03add 100644
--- a/loop/webui/src/web-components/sketch-tool-card.ts
+++ b/loop/webui/src/web-components/sketch-tool-card.ts
@@ -258,8 +258,8 @@
 
   static styles = css`
     pre {
-      background: black;
-      color: white;
+      background: rgb(236, 236, 236);
+      color: black;
       padding: 0.5em;
       border-radius: 4px;
     }
@@ -278,7 +278,7 @@
     }
     .result pre {
       margin-top: 0;
-      color: gray;
+      color: #555;
       border-radius: 0 0 4px 4px;
     }
   `;