message: Button: fixed stretched styles and removed 100% width for size="l"
diff: .Button--str {
  display: block;
  - max-width: 100%;
  - flex-grow: 1;
  - }
  -
  -.Button--str:first-child:last-child {
  width: 100%;
  + flex-grow: 1;
  + flex-basis: 0;
  }
  .Button--str .Button__in {
  }
  .Button--sz-l {
  - display: block;
  - width: 100%;
  padding: 0 20px;
  min-height: 44px;
  }
  