fix(hashicorp): check input before isValid

lib/versioning/hashicorp/index.ts

@@ -18,7 +18,7 @@ const isLessThanRange = (version: string, range: string): boolean =>
   npm.isLessThanRange(hashicorp2npm(version), hashicorp2npm(range));
 
 export const isValid = (input: string): string | boolean =>
-  npm.isValid(hashicorp2npm(input));
+  input && npm.isValid(hashicorp2npm(input));
 
 const matches = (version: string, range: string): boolean =>
   npm.matches(hashicorp2npm(version), hashicorp2npm(range));