Remove obsolete styles introduced with brave#2460

Addresses brave#10263

These styles were introduced on brave@ac2e6d1#diff-b6afd5ab48e47aa71ccacf98b2e44c42R49 without direction of usage. It is not possible to detect where they are / have been used. Let's revert it if we'll use those.

Auditors: @cezaraugusto

Test Plan:
1. Search your repo for `type="range"`
2. Make sure nothing is found

less/sortableTable.less

@@ -57,30 +57,6 @@ table.sortableTable {
       -webkit-font-smoothing: antialiased;
       position: relative;
       width: auto;
-
-      input[type='range'] {
-        background: transparent;
-        -webkit-appearance: none;
-        width: 90%;
-        margin: 0 0 0 20%;
-        outline: none;
-
-        &::-webkit-slider-runnable-track {
-          -webkit-appearance: none;
-          background: @gray25;
-          border-radius: 1000px;
-          height: 1em;
-        }
-
-        &::-webkit-slider-thumb {
-          -webkit-appearance: none;
-          background: linear-gradient(to bottom, @braveOrange, @braveDarkOrange);
-          width: 1em;
-          height: 1em;
-          border-radius: 50%;
-          box-shadow: 0 0 6px @black25;
-        }
-      }
     }
   }
   tr.rowHover:hover {