Apply suggestions from code review

Co-authored-by: Marcono1234 <[email protected]>

Author: atorralba

java/ql/src/semmle/code/java/frameworks/Mail.qll

@@ -20,7 +20,7 @@ class MailSessionGetInstanceMethod extends Method {
 }
 
 /**
- * A subtype of the class `org.apache.commons.mail.Mail`
+ * A subtype of the class `org.apache.commons.mail.Email`
  */
 class ApacheEmail extends Class {
   ApacheEmail() { this.getASupertype*().hasQualifiedName("org.apache.commons.mail", "Email") }

java/ql/src/semmle/code/java/security/Mail.qll

@@ -56,9 +56,7 @@ predicate hasSslCertificateCheck(VarAccess va) {
 private string getStringValue(Expr expr) {
   result = expr.(CompileTimeConstantExpr).getStringValue()
   or
-  result = getStringValue(expr.(AddExpr).getLeftOperand())
-  or
-  result = getStringValue(expr.(AddExpr).getRightOperand())
+  result = getStringValue(expr.(AddExpr).getAnOperand())
 }
 
 /**