fix: make Actions log parser support multiple line message encoding (#38659)

fix #38652


UI part (`.log-msg`) uses "white-space: break-spaces;" so the new line
can be correctly rendered.

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Signed-off-by: silverwind <me@silverwind.io>
Co-authored-by: silverwind <me@silverwind.io>

web_src/js/components/ActionRunJobView.vue

@@ -722,7 +722,7 @@ async function hashChangeListener() {
 
 .job-step-logs .job-log-line .log-msg {
   flex: 1;
-  white-space: break-spaces;
+  white-space: break-spaces; /* decoded commands like "::error::foo%0Abar" contain "\n" */
   margin-left: 12px;
   overflow-wrap: anywhere;
 }