Remove unneeded stylelint disables.

scss/_forms.scss

@@ -157,7 +157,6 @@ select.form-control {
   }
 }
 
-// stylelint-disable-next-line no-duplicate-selectors
 textarea.form-control {
   height: auto;
 }

scss/_transitions.scss

@@ -1,5 +1,3 @@
-// stylelint-disable selector-no-qualifying-type
-
 .fade {
   @include transition($transition-fade);
 

scss/mixins/_image.scss

@@ -20,7 +20,6 @@
 //
 // Short retina mixin for setting background-image and -size.
 
-// stylelint-disable indentation, media-query-list-comma-newline-after
 @mixin img-retina($file-1x, $file-2x, $width-1x, $height-1x) {
   background-image: url($file-1x);
 
@@ -29,7 +28,7 @@
   // There's no such thing as unprefixed min-device-pixel-ratio since it's nonstandard.
   // Compatibility info: https://caniuse.com/#feat=css-media-resolution
   @media only screen and (min-resolution: 192dpi), // IE9-11 don't support dppx
-  only screen and (min-resolution: 2dppx) { // Standardized
+    only screen and (min-resolution: 2dppx) { // Standardized
     background-image: url($file-2x);
     background-size: $width-1x $height-1x;
   }

scss/mixins/_reset-text.scss

@@ -5,7 +5,7 @@
   font-weight: $font-weight-normal;
   line-height: $line-height-base;
   text-align: left; // Fallback for where `start` is not supported
-  text-align: start; // stylelint-disable-line declaration-block-no-duplicate-properties
+  text-align: start;
   text-decoration: none;
   text-shadow: none;
   text-transform: none;