Speed up jnlp launch by 58%

[mgaffigan]

Speeds launch time by not requiring multiple round-trips for each plugin. Classpath with ballista remained identical. No obvious benefit to the historical design - presumed to be some Java Security Manager pipe dream.

Scenario	Before	After	% change
Cold cache, 100ms latency	8.9s	3.7s	↓58%
Warm cache, 100ms latency	5.8s	0.7s	↓87%

Mildly related: #197

[github-actions]

Test Results

  111 files  ±0    214 suites  ±0   6m 59s ⏱️ + 1m 12s
  651 tests  - 3    651 ✅  - 3  0 💤 ±0  0 ❌ ±0 
1 302 runs   - 6  1 302 ✅  - 6  0 💤 ±0  0 ❌ ±0 

Results for commit f6e8def. ± Comparison against base commit 8c1111b.

This pull request removes 3 tests.

com.mirth.connect.server.servlets.WebStartServletTest ‑ testDoGetExtension
com.mirth.connect.server.servlets.WebStartServletTest ‑ testDoGetExtensionModifiedURL
com.mirth.connect.server.servlets.WebStartServletTest ‑ testDoGetExtensionQueryParams

♻️ This comment has been updated with latest results.

[tonygermano]

Looks fine at a glance. I think the only thing we're really losing is the title and vendor information for the individual extensions.

Does this still allow launching from MCAL?

[mgaffigan]

Looks fine at a glance. I think the only thing we're really losing is the title and vendor information for the individual extensions.

The JNLP data is not shown anywhere that I can find in any of the launchers I've tested. The vendor information still shows normally in Extensions.

Does this still allow launching from MCAL?

It works fine, but MCAL is broken in main - I recommend we drop support entirely.