fix typos in documentation

Co-authored-by: Stephan Brandauer <kaeluka@github.com>

Author: erik-krogh

javascript/ql/lib/semmle/javascript/security/dataflow/InsecureTemporaryFileCustomizations.qll

@@ -71,7 +71,7 @@ module InsecureTemporaryFile {
     }
   }
 
-  /** A a string that references the global tmp dir. Seen as a source for insecure temporary file creation. */
+  /** A string that references the global tmp dir. Seen as a source for insecure temporary file creation. */
   class OSTempDir extends Source {
     OSTempDir() {
       this = DataFlow::moduleImport("os").getAMemberCall("tmpdir")

javascript/ql/src/Security/CWE-377/InsecureTemporaryFile.qhelp

@@ -12,7 +12,7 @@ case to remote code execution.
 <recommendation>
 <p>
 Use a well tested library like <a href="https://www.npmjs.com/package/tmp">tmp</a> 
-for creating temprary files. These libraries ensure both that the file is inaccesible
+for creating temporary files. These libraries ensure both that the file is inaccessible
 to other users and that the file does not already exist.
 </p>
 </recommendation>