feat: make mocha fail if it encounters 0 tests (#5981)
feat: make mocha fail if it encounters 0 tests (#5981)


rachel-fenichel/blockly,mark-friedman/blockly,google/blockly,rachel-fenichel/blockly,rachel-fenichel/blockly,google/blockly,rachel-fenichel/blockly,mark-friedman/blockly,google/blockly,mark-friedman/blockly,rachel-fenichel/blockly,rachel-fenichel/blockly,google/blockly,rachel-fenichel/blockly,google/blockly,mark-friedman/blockly,mark-friedman/blockly,google/blockly,mark-friedman/blockly,google/blockly