make tests pass (or skip) on darwin/arm64

[radeksimko]

Why?
Prior to this patch, many tests would fail for the same reason - attempt to install older version of Terraform which isn't available for darwin/arm64.

For example:

--- FAIL: TestDestroyCmd (0.08s)
    terraform_test.go:164: caching exec "v:0.12.31" in dir "/var/folders/9w/pddq2x656j76vxvsbhcs4nwr0000gq/T/tfinstall1718612104/v-0.12.31"
panic: error installing terraform "v:0.12.31": no ZIP archive found for terraform <nil> darwin/arm64 [recovered]
	panic: error installing terraform "v:0.12.31": no ZIP archive found for terraform <nil> darwin/arm64

goroutine 99 [running]:
testing.tRunner.func1.2({0x102b2d280, 0x1400038cb80})
	/opt/homebrew/Cellar/go/1.18.1/libexec/src/testing/testing.go:1389 +0x1c8
testing.tRunner.func1()
	/opt/homebrew/Cellar/go/1.18.1/libexec/src/testing/testing.go:1392 +0x384
panic({0x102b2d280, 0x1400038cb80})
	/opt/homebrew/Cellar/go/1.18.1/libexec/src/runtime/panic.go:838 +0x204
github.com/hashicorp/terraform-exec/tfexec/internal/testutil.(*TFCache).find(0x140002ca0c0, 0x14000003d40, {0x140004cc690, 0x9}, 0x14000077ea0)
	/Users/radeksimko/gopath/src/github.com/hashicorp/terraform-exec/tfexec/internal/testutil/tfcache_find.go:47 +0x374
github.com/hashicorp/terraform-exec/tfexec/internal/testutil.(*TFCache).Version(0x102b2d280?, 0x14000003d40, {0x1029fefa5, 0x7})
	/Users/radeksimko/gopath/src/github.com/hashicorp/terraform-exec/tfexec/internal/testutil/tfcache.go:61 +0x90
github.com/hashicorp/terraform-exec/tfexec.tfVersion(0x14000003d40?, {0x1029fefa5?, 0x14000067f48?})
	/Users/radeksimko/gopath/src/github.com/hashicorp/terraform-exec/tfexec/terraform_test.go:164 +0x88
github.com/hashicorp/terraform-exec/tfexec.TestDestroyCmd(0x14000003d40)
	/Users/radeksimko/gopath/src/github.com/hashicorp/terraform-exec/tfexec/destroy_test.go:13 +0x44
testing.tRunner(0x14000003d40, 0x102bf6820)
	/opt/homebrew/Cellar/go/1.18.1/libexec/src/testing/testing.go:1439 +0x110
created by testing.(*T).Run
	/opt/homebrew/Cellar/go/1.18.1/libexec/src/testing/testing.go:1486 +0x300
FAIL	github.com/hashicorp/terraform-exec/tfexec	6.097s

Alternatives

• We could build Terraform as part of running relevant tests. That would likely add to the test time, increase the complexity of already complex matrix of versions throughout all packages and risk that a particular version may simply not work on darwin/arm64 as it was never properly tested.
• We could update all tests to use v1.0.2+ which have darwin/arm64 builds, but there are still tests for older TF versions which may be useful to run.

Solution

I tried to strike the balance and bump TF version where it was possible/easy to do and skipped test where it wasn't.

---

I wish we could run any arm64 tests in CI, but AFAIK GitHub Actions don't offer that (yet).

[bflad]

Looks good to me, just some small non-blocking considerations 🚀