Update gotestsum to latest

[KCarretto]

CI: update gotestsum to latest to support go 1.25.0

The gotestsum library was pinned to v1.12.0 to support Go 1.23.4 (as v1.13.0 required Go 1.24). However, as our application has upgraded to Go 1.25.0, we can safely upgrade the gotestsum dependency to the latest version during the GitHub Actions Workflow (tests.yml). This fixes the workflow's tool installation step where it fails because gotestsum@v1.12.0 cannot be installed properly.

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PR created automatically by Jules for task 18159997377938067536 started by @KCarretto

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[github-actions]

Summary

Tests 📝	Passed ✅	Failed ❌	Skipped ⏭️	Other ❓	Flaky 🍂	Duration ⏱️
2430	2430	0	0	0	0	1ms

Previous Results

Build 🏗️	Result 🧪	Tests 📝	Passed ✅	Failed ❌	Skipped ⏭️	Other ❓	Flaky 🍂	Duration ⏱️
#1960	✅	2430	2430	0	0	0	0	not captured

Insights

Average Tests per Run	Total Flaky Tests	Total Failed	Slowest Test (p95)
2430	0	0	4m 53s

Test Changes

0 test added, 0 removed

Slowest Tests

Test 📝	Results 📊	Duration (avg) ⏱️	Duration (p95) ⏱️
eldritch-libfile: std::list_recent_impl::tests::test_list_recent_default_args	3	3m 24s	4m 53s
eldritch-libfile: std::list_recent_impl::tests::test_list_recent_default_args	3	3m 24s	4m 53s
eldritch-libfile: std::list_recent_impl::tests::test_list_recent_default_args	3	3m 24s	4m 53s
eldritch-libsys: std::dll_inject_impl::tests::test_dll_inject_simple	1	5.2s	5.2s
imix::bin/imix: tests::task_tests::test_task_eprint_behavior	3	3.0s	3.0s
imix::bin/imix: tests::task_tests::test_task_eprint_behavior	3	3.0s	3.0s
imix::bin/imix: tests::task_tests::test_task_eprint_behavior	3	3.0s	3.0s
imix::bin/imix: tests::task_tests::test_task_streaming_error	3	3.0s	3.0s
imix::bin/imix: tests::task_tests::test_task_streaming_error	3	3.0s	3.0s
imix::bin/imix: tests::task_tests::test_task_streaming_error	3	3.0s	3.0s

_{🎉 No failed tests in this run. | 🍂 No flaky tests in this run.}

Github Test Reporter by CTRF 💚