anchor.diff:  [source,eql]
   ----
   startsWith("regsvr32.exe", "regsvr32")  // returns true
  -startsWith("regsvr32.exe", "RegSvr32")  // returns true
   startsWith("regsvr32.exe", "explorer")  // returns false
   startsWith("", "")                      // returns true
   
  
positive.code: [[eql-fn-startswith]]
  === `startsWith`
  
  Returns `true` if a source string begins with a provided substring. Matching is
  case insensitive.
  
  [%collapsible]
  ====
  
negative.code: [[eql-fn-endswith]]
  === `endsWith`
  
  Returns `true` if a source string ends with a provided substring.
  
  [%collapsible]
  ====
  