[8.7] Bump go version to 1.19.8

[cmacknz]

What the summary says. Main is already at Go 1.20 so this targets 8.7.

[cmacknz]

Depends on elastic/golang-crossbuild#282

[elasticmachine]

💚 Build Succeeded

the below badges are clickable and redirect to their specific view in the CI or DOCS

Expand to view the summary

Build stats

• Start Time: 2023-04-19T01:38:56.325+0000

• Duration: 14 min 39 sec

Test stats 🧪

Test	Results
Failed	0
Passed	519
Skipped	1
Total	520

💚 Flaky test report

Tests succeeded.

🤖 GitHub comments

Expand to view the GitHub comments

To re-run your PR in the CI, just comment with:

• /test : Re-trigger the build.