build: Make it easier to manually run GWT tests from the IDE

[niloc132]

Summary from the task description:

Test wiring to run either unit or integration tests with a manual browser and an already-running server. This makes it easier to run a tests repeatedly, either one at a time or as a class/suite, without paying to start/stop selenium and deephaven each time. The port will remain constant at 8888 each run to let breakpoints continue to work across repeated runs.

To use this, first start a server on port 10000 with anonymous access enabled. Then, either select a test in IntelliJ to run using the manualGwtTest task, or invoke from the command line with info logging enabled and a specific test selected, e.g.:

./gradlew :web-client-api:manualGwtTest --info --tests io.deephaven.web.client.api.NullValueTestGwt

Click the URL that is printed out to run the test in your browser, or refresh an existing browser window.

[mofojed]

Sweet, this is great. Just a minor suggestion to clean up the wording a bit.

[mofojed]

Kind of confused when I first read this, suggest modifying the wording a bit.

Suggested change

	When the URL appears to run in your browser, click on it, or refresh an existing browser window.'''
	Click the URL that is printed out to run the test in your browser, or refresh an existing browser window.'''