refactor: Optimize code by using built-in constants in the standard l…

…ibrary (prometheus#2989)

Signed-off-by: coderwander <770732124@qq.com>
Signed-off-by: Vitaly Zhuravlev <v-zhuravlev@users.noreply.github.com>

collector/os_release.go

@@ -180,7 +180,7 @@ func (c *osReleaseCollector) UpdateStruct(path string) error {
 	}
 
 	if c.os.SupportEnd != "" {
-		c.supportEnd, err = time.Parse("2006-01-02", c.os.SupportEnd)
+		c.supportEnd, err = time.Parse(time.DateOnly, c.os.SupportEnd)
 
 		if err != nil {
 			return err