QLA: Color Contrast - Attempt number that is not selected

fixes: CNVS-18337

This edits the colors on toggle for attempts on the Quiz Log.
It should now be passing contrast.

Test Plan:

- Make sure Quiz Log Auditing feature is turned on
- Go to a quiz that has been completed by a student
- Go to Moderate Quiz
- Choose a student and then go to View Log
- The Attempts toggle should now be passing contrast ratio
requirements

Change-Id: Id2b1a1a6d7c61ed827d4f4bb7e1f5cd9ebfe8e0f
Reviewed-on: https://gerrit.instructure.com/48658
Reviewed-by: Ryan Shaw <ryan@instructure.com>
Product-Review: Colleen Palmer <colleen@instructure.com>
Tested-by: Jenkins
QA-Review: Nathan Rogowski <nathan@instructure.com>

client_apps/canvas_quizzes/apps/events/css/components/ic_quiz_inspector/session.scss

@@ -9,7 +9,7 @@
   box-shadow: 0 0 0 1px $borderColor;
   display: inline-block;
   border-radius: 2px;
-  background: $inactiveBg;
+  background: $canvas-neutral;
 }
 
 .ic-AttemptController__Attempt {
@@ -18,11 +18,10 @@
   text-align: center;
   line-height: 24px;
 
-  &, &:hover {
+  &, &:hover, &:focus {
     color: inherit;
     text-decoration: none;
-  }
-
+  }  
   &:first-of-type {
     border-radius: 2px 0 0 2px;
   }
@@ -38,9 +37,9 @@
   box-shadow: 0 0 0 1px $bg;
   margin-right: 1px;
   margin-left: 1px;
-
-  &, &:hover {
+  &, &:hover, &:focus {
     color: white;
     cursor: text;
+    text-decoration: none;
   }
 }