docs: public String getFingerprint() {
          RSAPublicKey key = InstanceIdentityProvider.RSA.getPublicKey();
          if (key == null) {
              return null;
          }
          // TODO replace with org.jenkinsci.remoting.util.KeyUtils once JENKINS-36871 changes are merged
          try {
              MessageDigest digest = MessageDigest.getInstance("MD5");
              digest.reset();
              byte[] bytes = digest.digest(key.getEncoded());
              StringBuilder result = new StringBuilder(Math.max(0, bytes.length * 3 - 1));
              for (int i = 0; i < bytes.length; i++) {
                  if (i > 0) {
                      result.append(':');
                  }
                  int b = bytes[i] & 0xFF;
                  result.append(Character.forDigit((b>>4)&0x0f, 16)).append(Character.forDigit(b&0xf, 16));
              }
              return result.toString();
          } catch (NoSuchAlgorithmException e) {
              throw new IllegalStateException("JLS mandates MD5 support");
          }
      }