r/pod: Represent update-ability of spec correctly

[radeksimko]

Fixes #20

Test results

make testacc TEST=./kubernetes TESTARGS='-run=TestAccKubernetesPod_'
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go test ./kubernetes -v -run=TestAccKubernetesPod_ -timeout 120m
=== RUN   TestAccKubernetesPod_basic
--- PASS: TestAccKubernetesPod_basic (11.48s)
=== RUN   TestAccKubernetesPod_updateForceNew
--- PASS: TestAccKubernetesPod_updateForceNew (83.46s)
=== RUN   TestAccKubernetesPod_importBasic
--- PASS: TestAccKubernetesPod_importBasic (5.99s)
=== RUN   TestAccKubernetesPod_with_pod_security_context
--- PASS: TestAccKubernetesPod_with_pod_security_context (5.71s)
=== RUN   TestAccKubernetesPod_with_container_liveness_probe_using_exec
--- PASS: TestAccKubernetesPod_with_container_liveness_probe_using_exec (39.94s)
=== RUN   TestAccKubernetesPod_with_container_liveness_probe_using_http_get
--- PASS: TestAccKubernetesPod_with_container_liveness_probe_using_http_get (5.03s)
=== RUN   TestAccKubernetesPod_with_container_liveness_probe_using_tcp
--- PASS: TestAccKubernetesPod_with_container_liveness_probe_using_tcp (20.05s)
=== RUN   TestAccKubernetesPod_with_container_lifecycle
--- PASS: TestAccKubernetesPod_with_container_lifecycle (5.12s)
=== RUN   TestAccKubernetesPod_with_container_security_context
--- PASS: TestAccKubernetesPod_with_container_security_context (5.53s)
=== RUN   TestAccKubernetesPod_with_volume_mount
--- PASS: TestAccKubernetesPod_with_volume_mount (21.52s)
=== RUN   TestAccKubernetesPod_with_cfg_map_volume_mount
--- PASS: TestAccKubernetesPod_with_cfg_map_volume_mount (13.94s)
=== RUN   TestAccKubernetesPod_with_resource_requirements
--- PASS: TestAccKubernetesPod_with_resource_requirements (11.65s)
=== RUN   TestAccKubernetesPod_with_empty_dir_volume
--- PASS: TestAccKubernetesPod_with_empty_dir_volume (6.35s)
=== RUN   TestAccKubernetesPod_with_secret_vol_items
--- PASS: TestAccKubernetesPod_with_secret_vol_items (13.62s)
=== RUN   TestAccKubernetesPod_with_nodeSelector
--- PASS: TestAccKubernetesPod_with_nodeSelector (20.07s)
PASS
ok  	github.com/terraform-providers/terraform-provider-kubernetes/kubernetes	269.548s

[tombuildsstuff]

one minor 🤔 otherwise LGTM :)

[tombuildsstuff]

with so many of these similar, you could argue this might make more sense as a custom validation function - but it's NBD

[radeksimko]

Hm, I see wdym, there's a lot of copy-pasted code, but I've learnt over time that duplication usually works better than abstractions in tests, b/c tests should be explicit and easy to read (w/out having to dig out details).