Fix the Changelog and extend tests to cover the hash of all-bits zero

Signed-off-by: TRodziewicz <tomasz.rodziewicz@mobica.com>
diff --git a/ChangeLog.d/issue1792.txt b/ChangeLog.d/issue1792.txt
index 39dbe5b..bd3d248 100644
--- a/ChangeLog.d/issue1792.txt
+++ b/ChangeLog.d/issue1792.txt
@@ -1,4 +1,4 @@
 Bugfix
-   * Fix a bug in ECDSA that would cause it to fail when the payload is all-bits
+   * Fix a bug in ECDSA that would cause it to fail when the hash is all-bits
      zero.
      Fixes #1792