Add flex shrink

sass/elements/form.sass

@@ -128,6 +128,7 @@
     margin-bottom: 5px
   +tablet
     flex-grow: 1
+    flex-shrink: 0
     margin-right: 20px
     padding-top: 7px
     text-align: right
@@ -162,6 +163,7 @@
           border-radius: 0 $radius $radius 0
       &.is-expanded
         flex-grow: 1
+        flex-shrink: 0
     &.has-addons-centered
       justify-content: center
     &.has-addons-right
@@ -171,6 +173,7 @@
       .input,
       .select
         flex-grow: 1
+        flex-shrink: 0
   &.has-icon
     & > .fa
       +fa(14px, 24px)
@@ -234,6 +237,7 @@
         margin-right: 10px
       &.is-expanded
         flex-grow: 1
+        flex-shrink: 0
     &.is-grouped-centered
       justify-content: center
     &.is-grouped-right
@@ -244,6 +248,7 @@
       & > .control
         display: flex
         flex-grow: 5
+        flex-shrink: 0
   &.is-loading
     &:after
       @extend .loader