Adding icon for Chapel Lang

Chapel is an open-source modern programming language designed for productive parallel computing at scale.
Chapel's homepage is at https://chapel-lang.org/
Chapel's repository is at https://github.com/chapel-lang/chapel and has over 1.6k stars

The svg logo is derived from Chapel's official logo: https://chapel-lang.org/logo.html
and follows the contributing guidelines
- Icon color fits material design and colors
- Icon has some space around it
- Matches chapel files with the `.chpl` extension
- Passes local tests

src/icons/fileIcons.ts

@@ -2359,5 +2359,6 @@ export const fileIcons: FileIcons = {
       name: 'mojo',
       fileExtensions: ['mojo', '🔥'],
     },
+    { name: 'chapel', fileExtensions: ['chpl'] },
   ],
 };

src/icons/languageIcons.ts

@@ -142,4 +142,5 @@ export const languageIcons: LanguageIcon[] = [
   { icon: { name: 'dart' }, ids: ['dart'] },
   { icon: { name: 'cadence' }, ids: ['cadence'] },
   { icon: { name: 'stylable' }, ids: ['stylable'] },
+  { icon: { name: 'chapel' }, ids: ['chapel'] },
 ];