Lower allowableValues threshold to display multiSelect

[hextraza]

This still needs rebasing + unit tests fixed, but it should allow all multivalued fields to use the multi select box.

[hextraza]

This should be merge-able. It'll enable multivalued select for any field with allowableValues.

[bbimber]

@hextraza: the code seems fine, but I dont understand why the test failed on the postgres agents, but not sqlserver. this suggests maybe some timing/intermittent failure? I restarted that test to see if it repros. from the screenshot, the dropdown was empty for IMPACT, with zero options. maybe a timing issue?

below is the stack:

org.openqa.selenium.NoSuchElementException: Expected condition failed: waiting for xpath=//li[normalize-space()="HIGH"] (tried for 10 second(s) with 100 milliseconds interval)
  at app//org.labkey.test.Locator.waitForElement(Locator.java:533)
  at app//org.labkey.test.Locator.waitForElement(Locator.java:509)
  at app//org.labkey.test.Locator.waitForElement(Locator.java:502)
  at app//org.labkey.test.WebDriverWrapper.waitForElement_aroundBody10(WebDriverWrapper.java:2363)
  at app//org.labkey.test.WebDriverWrapper.waitForElement_aroundBody11$advice(WebDriverWrapper.java:40)
  at app//org.labkey.test.WebDriverWrapper.waitForElement(WebDriverWrapper.java:1)
  at app//org.labkey.test.WebDriverWrapper.waitForElement_aroundBody8(WebDriverWrapper.java:2358)
  at app//org.labkey.test.WebDriverWrapper.waitForElement_aroundBody9$advice(WebDriverWrapper.java:40)
  at app//org.labkey.test.WebDriverWrapper.waitForElement(WebDriverWrapper.java:1)
  at app//org.labkey.test.tests.external.labModules.JBrowseTest.testLuceneSearchUI(JBrowseTest.java:1717)
  at app//org.labkey.test.tests.external.labModules.JBrowseTest.testFullTextSearch(JBrowseTest.java:1153)
  at app//org.labkey.test.tests.external.labModules.JBrowseTest.testSteps(JBrowseTest.java:111)
  at java.base@17.0.7/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  at java.base@17.0.7/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
  at java.base@17.0.7/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)