adding Alpine specific installations

vars/pkgs/alacritty.yml

@@ -1,21 +1,28 @@
 alacritty:
   version: 0.15.1
-  RedHat:
-    build_deps:
+  build_deps:
+    RedHat:
       - cmake
-      - freetype-devel
       - fontconfig-devel
+      - freetype-devel
+      - g++
       - libxcb-devel
       - libxkbcommon-devel
-      - g++
-  Debian:
-    build_deps:
+    Debian:
       - cmake
-      - pkg-config
-      - libfreetype6-dev
       - libfontconfig1-dev
+      - libfreetype6-dev
       - libxcb-xfixes0-dev
       - libxkbcommon-dev
+      - pkg-config
       - python3
+    Alpine:
+      - cmake
+      - fontconfig-dev
+      - freetype-dev
+      - g++
+      - libxcb-dev
+      - libxkbcommon-dev
+      - pkgconf
   cask:
     - alacritty