Grammar cleanup in SECURITY.md
Grammar cleanup in SECURITY.md

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doorkeeper-gem/doorkeeper,jasl/doorkeeper,mavenlink/doorkeeper,moneytree/doorkeeper,jasl/doorkeeper,outstand/doorkeeper,outstand/doorkeeper,moneytree/doorkeeper,outstand/doorkeeper,jasl/doorkeeper,mavenlink/doorkeeper,doorkeeper-gem/doorkeeper,doorkeeper-gem/doorkeeper,mavenlink/doorkeeper