Attach (recommended) or Link to PDF file here:
[test.pdf](https://github.com/mozilla/pdf.js/files/6270827/test.pdf)
Configuration:
- Web browser and its version:chrome 89
- Operating system and its version:win10
- PDF.js version: 2.4/2.7/2.8 no working
- Is a browser extension: no 

What is the expected behavior? (add screenshot)
![image](https://user-images.githubusercontent.com/18545199/113852392-1ae26080-97cf-11eb-9dc9-0cecf52d267b.png)

What went wrong? (add screenshot)
![1617791294(1)](https://user-images.githubusercontent.com/18545199/113852355-10c06200-97cf-11eb-8672-598750f1093a.jpg)


console this log : **FormatError: TrueType Collection does not contain "DCWGQU+CambriaMath" font** 

any solution?thanks
platformId === 3 &&
            encodingId === 1 &&
            (hasEncoding || !potentialTable)
          ) {
            useTable = true;
            if (!isSymbolicFont) {
              canBreak = true;
            }
          } else if (isSymbolicFont && platformId === 3 && encodingId === 0) {
            useTable = true;
            canBreak = true;
          }
          if (useTable) {
            potentialTable = {
              platformId,
              encodingId,
              offset,
            };
          }
          if (canBreak) {
            break;
          }
        }
        if (potentialTable) {
          file.pos = start + potentialTable.offset;
        }
        if (!potentialTable || file.peekByte() === -1) {
          warn("Could not find a preferred cmap table.");
          return {
            platformId: -1,