The cybersecurity stock's quarterly results helped build optimism about the industry's health.Shares of Zscaler (ZS -0.01%) rose 13.1% last month, according to data provided by S&P Global Market Intelligence. The company posted an impressive quarterly earnings report to start the month. Then the stock continued to move higher, thanks to momentum among cybersecurity stocks driven by additional promising data from members of the company's peer group.Bullish quarterly earnings report kicked off the monthZscale ...