fix gulp-sass vulnerabilities and update dependencies

vendor/fontawesome-free/scss/_icons.scss

@@ -525,6 +525,7 @@ readers do not read off random characters that represent icons */
 .#{$fa-css-prefix}-gift:before { content: fa-content($fa-var-gift); }
 .#{$fa-css-prefix}-gifts:before { content: fa-content($fa-var-gifts); }
 .#{$fa-css-prefix}-git:before { content: fa-content($fa-var-git); }
+.#{$fa-css-prefix}-git-alt:before { content: fa-content($fa-var-git-alt); }
 .#{$fa-css-prefix}-git-square:before { content: fa-content($fa-var-git-square); }
 .#{$fa-css-prefix}-github:before { content: fa-content($fa-var-github); }
 .#{$fa-css-prefix}-github-alt:before { content: fa-content($fa-var-github-alt); }
@@ -1100,6 +1101,7 @@ readers do not read off random characters that represent icons */
 .#{$fa-css-prefix}-squarespace:before { content: fa-content($fa-var-squarespace); }
 .#{$fa-css-prefix}-stack-exchange:before { content: fa-content($fa-var-stack-exchange); }
 .#{$fa-css-prefix}-stack-overflow:before { content: fa-content($fa-var-stack-overflow); }
+.#{$fa-css-prefix}-stackpath:before { content: fa-content($fa-var-stackpath); }
 .#{$fa-css-prefix}-stamp:before { content: fa-content($fa-var-stamp); }
 .#{$fa-css-prefix}-star:before { content: fa-content($fa-var-star); }
 .#{$fa-css-prefix}-star-and-crescent:before { content: fa-content($fa-var-star-and-crescent); }

vendor/fontawesome-free/scss/_variables.scss

@@ -5,7 +5,7 @@ $fa-font-path:                "../webfonts" !default;
 $fa-font-size-base:           16px !default;
 $fa-font-display:             auto !default;
 $fa-css-prefix:               fa !default;
-$fa-version:                  "5.8.1" !default;
+$fa-version:                  "5.8.2" !default;
 $fa-border-color:             #eee !default;
 $fa-inverse:                  #fff !default;
 $fa-li-width:                 2em !default;
@@ -540,6 +540,7 @@ $fa-var-ghost: \f6e2;
 $fa-var-gift: \f06b;
 $fa-var-gifts: \f79c;
 $fa-var-git: \f1d3;
+$fa-var-git-alt: \f841;
 $fa-var-git-square: \f1d2;
 $fa-var-github: \f09b;
 $fa-var-github-alt: \f113;
@@ -1115,6 +1116,7 @@ $fa-var-square-root-alt: \f698;
 $fa-var-squarespace: \f5be;
 $fa-var-stack-exchange: \f18d;
 $fa-var-stack-overflow: \f16c;
+$fa-var-stackpath: \f842;
 $fa-var-stamp: \f5bf;
 $fa-var-star: \f005;
 $fa-var-star-and-crescent: \f699;

vendor/fontawesome-free/scss/brands.scss

@@ -1,5 +1,5 @@
 /*!
- * Font Awesome Free 5.8.1 by @fontawesome - https://fontawesome.com
+ * Font Awesome Free 5.8.2 by @fontawesome - https://fontawesome.com
  * License - https://fontawesome.com/license/free (Icons: CC BY 4.0, Fonts: SIL OFL 1.1, Code: MIT License)
  */
 @import 'variables';

vendor/fontawesome-free/scss/fontawesome.scss

@@ -1,5 +1,5 @@
 /*!
- * Font Awesome Free 5.8.1 by @fontawesome - https://fontawesome.com
+ * Font Awesome Free 5.8.2 by @fontawesome - https://fontawesome.com
  * License - https://fontawesome.com/license/free (Icons: CC BY 4.0, Fonts: SIL OFL 1.1, Code: MIT License)
  */
 @import 'variables';

vendor/fontawesome-free/scss/regular.scss

@@ -1,5 +1,5 @@
 /*!
- * Font Awesome Free 5.8.1 by @fontawesome - https://fontawesome.com
+ * Font Awesome Free 5.8.2 by @fontawesome - https://fontawesome.com
  * License - https://fontawesome.com/license/free (Icons: CC BY 4.0, Fonts: SIL OFL 1.1, Code: MIT License)
  */
 @import 'variables';

vendor/fontawesome-free/scss/solid.scss

@@ -1,5 +1,5 @@
 /*!
- * Font Awesome Free 5.8.1 by @fontawesome - https://fontawesome.com
+ * Font Awesome Free 5.8.2 by @fontawesome - https://fontawesome.com
  * License - https://fontawesome.com/license/free (Icons: CC BY 4.0, Fonts: SIL OFL 1.1, Code: MIT License)
  */
 @import 'variables';

vendor/fontawesome-free/scss/v4-shims.scss

@@ -1,5 +1,5 @@
 /*!
- * Font Awesome Free 5.8.1 by @fontawesome - https://fontawesome.com
+ * Font Awesome Free 5.8.2 by @fontawesome - https://fontawesome.com
  * License - https://fontawesome.com/license/free (Icons: CC BY 4.0, Fonts: SIL OFL 1.1, Code: MIT License)
  */
 @import 'variables';