Update SCSS-Lint dependency

[tagliala]

SCSS-Lint 0.49.0 modifies Shorthand linter to report lint if a shorthand
of a length not specified in the allowed_shorthands option is used.

New defaults include "4" in the list of allowed shorthands, so we are changing our configuration accordingly.

Ref: sds/scss-lint@e283d16

[tagliala]

Note that SCSS-Lint 0.49.0 will find some lints when used with the old configuration:

$ grunt scsslint
Running "scsslint:core" (scsslint) task
Running scss-lint on core
scss/_custom-forms.scss:145:12 [W] Shorthand: Shorthands of length `4` are not allowed. Value was `$custom-select-padding-y $custom-select-padding-x + $custom-select-indicator-padding $custom-select-padding-y $custom-select-padding-x`
scss/_tooltip.scss:38:21 [W] Shorthand: Shorthands of length `4` are not allowed. Value was `$tooltip-arrow-width $tooltip-arrow-width $tooltip-arrow-width 0`
scss/_tooltip.scss:64:21 [W] Shorthand: Shorthands of length `4` are not allowed. Value was `$tooltip-arrow-width 0 $tooltip-arrow-width $tooltip-arrow-width`

[cvrebert]

X-Ref: stylelint/stylelint#1402

[cvrebert]

Thanks!