Consolidate Elastic APM dependencies

[watson]

APM Synthtrace added a direct dependency to elastic-apm-http-client in #136530. This wasn't kept up to date with the client used by the main elastic-apm-node dependency when that was recently upgraded. This PR fixes that and also consolidates the elastic-apm-node dependency to only have one version (the other was depended upon by the backtrace dependency, which luckily is only used in development).

Update 1: There were a compatibility issue with the newest version of elastic-apm-node and backport, so I had to slightly walk this one back. I've updated backport as well to meet half way.

Update 2: After the discussion below, I've removed the APM Synthtrace dependency on elastic-apm-http-client as it was no longer used

The only breaking change in the elastic-apm-http-client upgrade is that the hostname config property is now named configuredHostname according to the CHANGELOG.md. So I think the change I made is sufficient. But we should probably get someone with knowledge of APM Synthtrace to review.

[elasticmachine]

Pinging @elastic/apm-ui (Team:APM)

[elasticmachine]

Pinging @elastic/kibana-operations (Team:Operations)

[trentm]

Update: There were a compatibility issue with the newest version of elastic-apm-node and backport, so I had to slightly walk this one back. I've updated backport as well to meet half way.

Was there some indication of what that compat issue was? I see sorenlouv/backport#465 that locked the elastic-apm-node dep version for backport, but no indication of the issue. I suppose I could try it myself. :)

[trentm]

I suppose I could try it myself. :)

I've opened sorenlouv/backport#467 to have it support the latest elastic-apm-node version.
@sqren Perhaps you could review, merge, do a release of backport with that; then this PR could update to the new backport version. However, that could be done independently. Up to @watson if you want to wait for that.

[watson]

@trentm Søren is on PTO, so I'll prefer merging this one now and then just make a follow up PR once he's back and can address your PR.

@elastic/apm-ui Can I please get a review from one of you with the recent changes?

[kibana-ci]

💚 Build Succeeded

• Buildkite Build
• Commit: c894686

Metrics [docs]

Unknown metric groups

ESLint disabled line counts

id	before	after	diff
@kbn/apm-synthtrace	6	5	-1

Total ESLint disabled count

id	before	after	diff
@kbn/apm-synthtrace	8	7	-1

History

• 💚 Build #145478 succeeded 876ed72
• 💔 Build #145412 failed b176914

To update your PR or re-run it, just comment with:
@elasticmachine merge upstream

cc @watson

[achyutjhunjhunwala]

APM changes LGTM 👍🏼

[kibanamachine]

💔 All backports failed

Status	Branch	Result
❌	7.17	Backport failed because of merge conflicts
❌	8.9	Backport failed because of merge conflicts

Manual backport

To create the backport manually run:

node scripts/backport --pr 162686

Questions ?

Please refer to the Backport tool documentation

[watson]

The backports is turning out to be too complicated and multiple PRs needs to be backported as one unit. I'll do them manually instead and remove the label