Update lodash dependency to remove audit errors

[dawidgarus]

Old dependencies causes npm audit errors:

  High            Prototype Pollution

  Package         lodash

  Patched in      >=4.17.11

  Dependency of   b4495b4ad9c96cc5a41e3d1f66888ae56995691bffb77073e348c2d98c7…

  Path            b4495b4ad9c96cc5a41e3d1f66888ae56995691bffb77073e348c2d98c7…
                  > gulp-responsive-images > lodash

  More info       https://nodesecurity.io/advisories/782


  High            Prototype Pollution

  Package         lodash

  Patched in      >=4.17.12

  Dependency of   b4495b4ad9c96cc5a41e3d1f66888ae56995691bffb77073e348c2d98c7…

  Path            b4495b4ad9c96cc5a41e3d1f66888ae56995691bffb77073e348c2d98c7…
                  > gulp-responsive-images > lodash

  More info       https://nodesecurity.io/advisories/1065


  Low             Prototype Pollution

  Package         lodash

  Patched in      >=4.17.5

  Dependency of   b4495b4ad9c96cc5a41e3d1f66888ae56995691bffb77073e348c2d98c7…

  Path            b4495b4ad9c96cc5a41e3d1f66888ae56995691bffb77073e348c2d98c7…
                  > gulp-responsive-images > lodash

  More info       https://nodesecurity.io/advisories/577