chore(docs): rephrase sentence for grammatical correctness (#1620)

Change Text from "Passing anything other than a string is an error." to "Passing anything other than a string will result in an error."

Author: prahaladbelavadi

README.md

@@ -14,7 +14,7 @@ A library of string validators and sanitizers.
 **This library validates and sanitizes strings only.**
 
 If you're not sure if your input is a string, coerce it using `input + ''`.
-Passing anything other than a string is an error.
+Passing anything other than a string will result in an error.
 
 ## Installation and Usage