docs: API documentation fixes

Change-Id: I1088a156c9ac055f974900454647dcb9a7b7ec54
Refs: #3210
diff --git a/src/util/digest.hpp b/src/util/digest.hpp
index 0fdb3a3..ea1538e 100644
--- a/src/util/digest.hpp
+++ b/src/util/digest.hpp
@@ -64,7 +64,7 @@
   Digest();
 
   /**
-   * @brief Create digest of the input stream @p
+   * @brief Create digest of the input stream @p is
    * @param is input stream
    */
   explicit