Merge pull request #4117 from jsoref/JENKINS-58520

[JENKINS-58520] - Make new Jenkins version notification noticeable in administrative monitors

core/src/filter/resources/hudson/model/UpdateCenter/CoreUpdateMonitor/message.properties

@@ -20,7 +20,7 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 # THE SOFTWARE.
 
-NewVersionAvailable=New version of Jenkins ({0}) is available for <a href="{1}">download</a> \
+NewVersionAvailable=<strong>New version of Jenkins ({0}) is available</strong> for <a href="{1}">download</a> \
   (<a href="{2}">changelog</a>).
 ChangelogUrl=${changelog.url}
 UpgradeComplete=Upgrade to Jenkins {0} is complete, awaiting <a href="{1}/safeRestart">restart</a>.