refactor: update languages JSON (#4162)

Co-authored-by: qwerty541 <53787217+qwerty541@users.noreply.github.com>

Author: github-actions[bot]

src/common/languageColors.json

@@ -238,6 +238,7 @@
     "IDL": "#a3522f",
     "IGOR Pro": "#0000cc",
     "INI": "#d1dbe0",
+    "ISPC": "#2D68B1",
     "Idris": "#b30000",
     "Ignore List": "#000000",
     "ImageJ Macro": "#99AAFF",
@@ -491,6 +492,7 @@
     "Shen": "#120F14",
     "Simple File Verification": "#C9BFED",
     "Singularity": "#64E6AD",
+    "Slang": "#1fbec9",
     "Slash": "#007eff",
     "Slice": "#003fa2",
     "Slim": "#2b2b2b",