Grammars fail to apply external includes from captures property

Issue Type: Bug

As I've been trying fix some issues with the SCSS/SASS grammars I've notices that including patterns from the CSS grammar does not work from the captures property.

Here I have a grammar that replicates the issue. You'll notice the external include for source.css#color-keywords is not applied, but the replicated internal include is.

{
  "name": "SASS",
  "scopeName": "source.sass",
  "patterns": [
    {
      "name": "variable.interpolation.sass",
      "match": "(#{)(.*)(})",
      "captures": {
        "1": {
          "name": "punctuation.definition.interpolation.begin.bracket.round.sass"
        },
        "2": {
          "patterns": [
            {
              "include": "#strings"
            },
            {
              "include": "source.css#color-keywords"
            }
          ]
        },
        "3": {
          "name": "punctuation.definition.interpolation.end.bracket.round.sass"
        }
      }
    },
    {
      "name": "variable.interpolation.sass",
      "match": "(\\$\\()(.*)(\\))",
      "captures": {
        "1": {
          "name": "punctuation.definition.interpolation.begin.bracket.curly.sass"
        },
        "2": {
          "patterns": [
            {
              "include": "#strings"
            },
            {
              "include": "#color-keywords"
            }
          ]
        },
        "3": {
          "name": "punctuation.definition.interpolation.end.bracket.curly.sass"
        }
      }
    }
  ],
  "repository": {
    "strings": {
      "patterns": [
        {
          "name": "string.quoted.single.sass",
          "begin": "'",
          "end": "'",
          "beginCaptures": {
            "0": {
              "name": "punctuation.definition.string.begin.sass"
            }
          },
          "endCaptures": {
            "0": {
              "name": "punctuation.definition.string.end.sass"
            }
          }
        },
        {
          "name": "string.quoted.double.sass",
          "begin": "\"",
          "end": "\"",
          "beginCaptures": {
            "0": {
              "name": "punctuation.definition.string.begin.sass"
            }
          },
          "endCaptures": {
            "0": {
              "name": "punctuation.definition.string.end.sass"
            }
          }
        }
      ]
    },
    "color-keywords": {
      "patterns": [
        {
          "match": "(?i)(?<![\\w-])(aqua|black|blue|fuchsia|gray|green|lime|maroon|navy|olive|orange|purple|red|silver|teal|white|yellow)(?![\\w-])",
          "name": "support.constant.color.w3c-standard-color-name.css"
        },
        {
          "match": "(?xi) (?<![\\w-])\n(aliceblue|antiquewhite|aquamarine|azure|beige|bisque|blanchedalmond|blueviolet|brown|burlywood\n|cadetblue|chartreuse|chocolate|coral|cornflowerblue|cornsilk|crimson|cyan|darkblue|darkcyan\n|darkgoldenrod|darkgray|darkgreen|darkgrey|darkkhaki|darkmagenta|darkolivegreen|darkorange\n|darkorchid|darkred|darksalmon|darkseagreen|darkslateblue|darkslategray|darkslategrey|darkturquoise\n|darkviolet|deeppink|deepskyblue|dimgray|dimgrey|dodgerblue|firebrick|floralwhite|forestgreen\n|gainsboro|ghostwhite|gold|goldenrod|greenyellow|grey|honeydew|hotpink|indianred|indigo|ivory|khaki\n|lavender|lavenderblush|lawngreen|lemonchiffon|lightblue|lightcoral|lightcyan|lightgoldenrodyellow\n|lightgray|lightgreen|lightgrey|lightpink|lightsalmon|lightseagreen|lightskyblue|lightslategray\n|lightslategrey|lightsteelblue|lightyellow|limegreen|linen|magenta|mediumaquamarine|mediumblue\n|mediumorchid|mediumpurple|mediumseagreen|mediumslateblue|mediumspringgreen|mediumturquoise\n|mediumvioletred|midnightblue|mintcream|mistyrose|moccasin|navajowhite|oldlace|olivedrab|orangered\n|orchid|palegoldenrod|palegreen|paleturquoise|palevioletred|papayawhip|peachpuff|peru|pink|plum\n|powderblue|rebeccapurple|rosybrown|royalblue|saddlebrown|salmon|sandybrown|seagreen|seashell\n|sienna|skyblue|slateblue|slategray|slategrey|snow|springgreen|steelblue|tan|thistle|tomato\n|transparent|turquoise|violet|wheat|whitesmoke|yellowgreen)\n(?![\\w-])",
          "name": "support.constant.color.w3c-extended-color-name.css"
        },
        {
          "match": "(?i)(?<![\\w-])currentColor(?![\\w-])",
          "name": "support.constant.color.current.css"
        },
        {
          "match": "(?xi) (?<![\\w-])\n(ActiveBorder|ActiveCaption|AppWorkspace|Background|ButtonFace|ButtonHighlight|ButtonShadow\n|ButtonText|CaptionText|GrayText|Highlight|HighlightText|InactiveBorder|InactiveCaption\n|InactiveCaptionText|InfoBackground|InfoText|Menu|MenuText|Scrollbar|ThreeDDarkShadow\n|ThreeDFace|ThreeDHighlight|ThreeDLightShadow|ThreeDShadow|Window|WindowFrame|WindowText)\n(?![\\w-])",
          "name": "invalid.deprecated.color.system.css"
        }
      ]
    }
  }
}

VS Code version: Code 1.50.1 (d2e414d9e4239a252d1ab117bd7067f125afd80a, 2020-10-13T14:53:05.704Z)
OS version: Darwin x64 19.6.0