Update visibility_off to conform to icon standards

Needed darker grey to differentiate between on/off states

Fixes https://gitlab.com/kicad/code/kicad/issues/12338

resources/bitmaps_png/sources/dark/visibility_off.svg

@@ -12,7 +12,7 @@
    viewBox="0 0 24 24"
    version="1.1"
    sodipodi:docname="visibility_off.svg"
-   inkscape:version="1.0.2 (1.0.2+r75+1)">
+   inkscape:version="1.0.2 (e86c870879, 2021-01-15)">
   <sodipodi:namedview
      pagecolor="#ffffff"
      bordercolor="#666666"
@@ -22,16 +22,16 @@
      guidetolerance="10"
      inkscape:pageopacity="0"
      inkscape:pageshadow="2"
-     inkscape:window-width="2560"
-     inkscape:window-height="1371"
+     inkscape:window-width="1568"
+     inkscape:window-height="1202"
      id="namedview30"
      showgrid="true"
      inkscape:zoom="19.771793"
-     inkscape:cx="3.3259971"
-     inkscape:cy="13"
-     inkscape:window-x="0"
-     inkscape:window-y="0"
-     inkscape:window-maximized="1"
+     inkscape:cx="-2.7809473"
+     inkscape:cy="7.9982237"
+     inkscape:window-x="7704"
+     inkscape:window-y="146"
+     inkscape:window-maximized="0"
      inkscape:document-rotation="0"
      inkscape:current-layer="Слой_1">
     <inkscape:grid
@@ -85,17 +85,17 @@
      cy="12"
      r="12"
      id="circle27637"
-     style="fill:#545454;fill-opacity:1" />
+     style="fill:#404040;fill-opacity:1" />
   <path
      class="cls-2"
      d="m 21.7206,12 c 0,0 -4.3521,5.2839 -9.7206,5.2839 C 6.6315,17.2839 2.2794,12 2.2794,12 2.2794,12 6.6315,6.7159 12,6.7159 17.3685,6.7159 21.7206,12 21.7206,12 Z"
      id="path27639"
-     style="fill:#e0e0e0;fill-opacity:1" />
+     style="fill:#848484;fill-opacity:1" />
   <path
      class="cls-1"
      d="m 8.8057,13.6562 a 3.5983,3.5983 0 0 1 5.2052,-4.6414 c 0.9567,0.647 -4.6063,5.7963 -5.2052,4.6414 z"
      id="path27641"
-     style="fill:#545454;fill-opacity:1" />
+     style="fill:#404040;fill-opacity:1" />
   <rect
      class="cls-1"
      x="-8.0458632"
@@ -104,10 +104,10 @@
      height="3.4266"
      transform="rotate(-44.974)"
      id="rect27643"
-     style="fill:#545454;fill-opacity:1" />
+     style="fill:#404040;fill-opacity:1" />
   <path
      class="cls-3"
      d="m 5.0934,18.8622 a 1.0715,1.0715 0 0 1 -0.7576,-1.83 L 16.9935,4.3622 A 1.0723632,1.0723632 0 1 1 18.5088,5.88 L 5.8511,18.5491 a 1.0668,1.0668 0 0 1 -0.7577,0.3131 z"
      id="path27645"
-     style="fill:#e0e0e0;fill-opacity:1" />
+     style="fill:#848484;fill-opacity:1" />
 </svg>