nit: made the hardcoded string o var

Author: sumandas0

webapp/src/main/java/org/apache/atlas/web/filters/AuditFilter.java

@@ -60,6 +60,7 @@ public class AuditFilter implements Filter {
     private static final Logger AUDIT_LOG = LoggerFactory.getLogger("AUDIT");
     public static final String TRACE_ID   = "trace_id";
     public static final String X_ATLAN_REQUEST_ID = "X-Atlan-Request-Id";
+    public static final String X_ATLAN_CLIENT_ORIGIN = "X-Atlan-Client-Origin";
     private boolean deleteTypeOverrideEnabled                = false;
     private boolean createShellEntityForNonExistingReference = false;
 
@@ -103,7 +104,7 @@ public void doFilter(ServletRequest request, ServletResponse response, FilterCha
             requestContext.setCreateShellEntityForNonExistingReference(createShellEntityForNonExistingReference);
             requestContext.setForwardedAddresses(AtlasAuthorizationUtils.getForwardedAddressesFromRequest(httpRequest));
             requestContext.setSkipFailedEntities(skipFailedEntities);
-            requestContext.setClientOrigin(httpRequest.getHeader("X-Atlan-Client-Origin"));
+            requestContext.setClientOrigin(httpRequest.getHeader(X_ATLAN_CLIENT_ORIGIN));
             requestContext.setMetricRegistry(metricsRegistry);
             MDC.put(TRACE_ID, internalRequestId);
             MDC.put(X_ATLAN_REQUEST_ID, ofNullable(httpRequest.getHeader(X_ATLAN_REQUEST_ID)).orElse(EMPTY));