support extensions in update_builder command

[mhdawson]

Summary

Add handling of extension sections in builder toml files
Refs: #294

Use Cases

Supports update of toml files for builders that use extensions

Checklist

• I have viewed, signed, and submitted the Contributor License Agreement.
• I have linked issue(s) that this PR should close using keywords or the Github UI (See docs)
• I have added an integration test, if necessary.
• I have reviewed the styleguide for guidance on my code quality.
• I'm happy with the commit history on this PR (I have rebased/squashed as needed).

[mhdawson]

NOTE: All tests in CI passed so I guess this can be ignored :)

I'm not sure why some of the changes in the test are needed, for example:

[[buildpacks]]
	-uri = "docker://REGISTRY-URI/paketobuildpacks/nodejs:0.20.22"
  +uri = "docker://REGISTRY-URI/paketobuildpacks/nodejs:0.20.22"
  version = "0.20.22"

As I would have expected tests to fail without that change before, they do fail on my local runs without those changes so not quite sure what is going on.

In my local Fedora environment there are some failures in the tests without of my changes. I'm assuming that is something environment related and that they won't show in the CI. These are the failures I see without any of my changes:

[user1@fedora jam]$ !cat
cat temp1 |grep FAIL
--- FAIL: TestJam (30.15s)
    --- FAIL: TestJam/jam (26.31s)
        --- FAIL: TestJam/jam/create-stack/builds_an_example_stack (7.45s)
FAIL
FAIL	github.com/paketo-buildpacks/jam/v2/integration	30.160s
--- FAIL: TestUnitIHOP (19.45s)
    --- FAIL: TestUnitIHOP/ihop (17.58s)
        --- FAIL: TestUnitIHOP/ihop/Client/Build/failure_cases/when_the_image_build_fails/returns_an_error (0.35s)
FAIL
FAIL	github.com/paketo-buildpacks/jam/v2/internal/ihop	19.467s
FAIL

[robdimsdale]

LGTM. I have one clarifying - and non-blocking - question in line

[robdimsdale]

NOTE: All tests in CI passed so I guess this can be ignored :)

I'm not sure why some of the changes in the test are needed, for example:

[[buildpacks]]
	-uri = "docker://REGISTRY-URI/paketobuildpacks/nodejs:0.20.22"
  +uri = "docker://REGISTRY-URI/paketobuildpacks/nodejs:0.20.22"
  version = "0.20.22"

As I would have expected tests to fail without that change before, they do fail on my local runs without those changes so not quite sure what is going on.

In my local Fedora environment there are some failures in the tests without of my changes. I'm assuming that is something environment related and that they won't show in the CI. These are the failures I see without any of my changes:

[user1@fedora jam]$ !cat
cat temp1 |grep FAIL
--- FAIL: TestJam (30.15s)
    --- FAIL: TestJam/jam (26.31s)
        --- FAIL: TestJam/jam/create-stack/builds_an_example_stack (7.45s)
FAIL
FAIL	github.com/paketo-buildpacks/jam/v2/integration	30.160s
--- FAIL: TestUnitIHOP (19.45s)
    --- FAIL: TestUnitIHOP/ihop (17.58s)
        --- FAIL: TestUnitIHOP/ihop/Client/Build/failure_cases/when_the_image_build_fails/returns_an_error (0.35s)
FAIL
FAIL	github.com/paketo-buildpacks/jam/v2/internal/ihop	19.467s
FAIL

I've noticed that some jam tests fail on one of my machines due to a different umask that what is assumed by the tests. I didn't dig into whether this was the same tests failures you saw, but I just wanted to let you know.