Remove waitForUploads workaround after flow-components release

[mcollovati]

AppViewIT test in test-spring-security-flow module currently has a workaround for a bug in Upload testbench element waitForUploads method.

The bug has been fixed, but not yet released.
Since the Flow test module uses a stable flow-component version, the workaround could be removed only after the flow-components release.

The current code in flow test module

upload.upload(tmpFile, 0);
waitForUploads(upload, 60);

should become simply

upload.upload(tmpFile);

The bugfix in flow-components has been backported to 24.6 and 24.5, so in Flow the workaround can be removed only on the same branches (not in 24.4).