patch 8.2.0497: too verbose output from the asan build in Travis

Problem:    Too verbose output from the asan build in Travis.
Solution:   Filter out suppression messages. (Ozaki Kiichi, closes #5874)

.travis.yml

@@ -100,7 +100,7 @@ _anchors:
     # Update pyenv to fix the error "/opt/pyenv/libexec/pyenv: line 43: cd: asan_symbolize-6.0: Not a directory".
     # https://github.com/pyenv/pyenv/issues/580
     - (cd "${PYENV_ROOT}" && git fetch -p origin && git checkout "$(git rev-list --tags -n1)") &>/dev/null || true
-    - find . -type f -name 'asan.*' -size +0 2>/dev/null | xargs -I{} -n1 -t asan_symbolize -l{}
+    - find . -type f -name 'asan.*' -size +0 2>/dev/null | xargs grep -l '^==[[:digit:]]*==ERROR:' | xargs -I{} -n1 -t asan_symbolize -l{}
 
 branches:
   except:

src/version.c

@@ -738,6 +738,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    497,
 /**/
     496,
 /**/