Replace invalid US-ASCII character "\xE2")

Replace invalid US-ASCII character "\xE2") '—' => '-'

less/grid.less

@@ -76,7 +76,7 @@
 // Grid classes for extra small devices like smartphones. No offset, push, or
 // pull classes are present here due to the size of the target.
 //
-// Note that `.col-xs-12` doesn't get floated on purpose—there's no need since
+// Note that `.col-xs-12` doesn't get floated on purpose-there's no need since
 // it's full-width.
 
 .col-xs-1,
@@ -111,7 +111,7 @@
 // Columns, offsets, pushes, and pulls for the small device range, from phones
 // to tablets.
 //
-// Note that `.col-sm-12` doesn't get floated on purpose—there's no need since
+// Note that `.col-sm-12` doesn't get floated on purpose-there's no need since
 // it's full-width.
 
 @media (min-width: @screen-sm) {
@@ -189,7 +189,7 @@
 //
 // Columns, offsets, pushes, and pulls for the desktop device range.
 //
-// Note that `.col-md-12` doesn't get floated on purpose—there's no need since
+// Note that `.col-md-12` doesn't get floated on purpose-there's no need since
 // it's full-width.
 
 @media (min-width: @screen-md) {
@@ -269,7 +269,7 @@
 //
 // Columns, offsets, pushes, and pulls for the large desktop device range.
 //
-// Note that `.col-lg-12` doesn't get floated on purpose—there's no need since
+// Note that `.col-lg-12` doesn't get floated on purpose-there's no need since
 // it's full-width.
 
 @media (min-width: @screen-lg-desktop) {