feat: check readonly filesystem on containers

[juev]

refactor: consolidate duplicate code
added checks for readonly filesystem on containers (fixed: deckhouse/deckhouse#4690)
remove panics

[juev]

Checked locally, partial result:

🐒 [#k8s-resources]
        Message - Container's SecurityContext has `ReadOnlyRootFilesystem: false`, but it must be `true`
        Object  - kind = Deployment ; name = terraform-auto-converger ; namespace = d8-system ; container = converger
        Module  - terraform-manager

🐒 [#k8s-resources]
        Message - Container's SecurityContext has `ReadOnlyRootFilesystem: false`, but it must be `true`
        Object  - kind = Deployment ; name = terraform-state-exporter ; namespace = d8-system ; container = exporter
        Module  - terraform-manager

🐒 [#images]
        Message - Use `from:` or `fromImage:` and `final: false` directives instead of `artifact:` in the werf file
        Object  - /Users/devsyukov/src/github.com/deckhouse/deckhouse-test-modules/modules/500-upmeter/images/smoke-mini/werf.inc.yaml
        Module  - upmeter
        Value   - .Images.BASE_GOLANG_20_ALPINE

🐒 [#images]
        Message - Use `from:` or `fromImage:` and `final: false` directives instead of `artifact:` in the werf file
        Object  - /Users/devsyukov/src/github.com/deckhouse/deckhouse-test-modules/modules/500-upmeter/images/status/werf.inc.yaml
        Module  - upmeter
        Value   - node:14-alpine3.12@sha256:426384fb33a11d27dbbdc545f39bb8daacd3e7db7c60b52cd6bc0597e0045b8d

🐒 [#images]
        Message - Use `from:` or `fromImage:` and `final: false` directives instead of `artifact:` in the werf file
        Object  - /Users/devsyukov/src/github.com/deckhouse/deckhouse-test-modules/modules/500-upmeter/images/upmeter/werf.inc.yaml
        Module  - upmeter
        Value   - .Images.BASE_GOLANG_20_ALPINE

🐒 [#images]
        Message - Use `from:` or `fromImage:` and `final: false` directives instead of `artifact:` in the werf file
        Object  - /Users/devsyukov/src/github.com/deckhouse/deckhouse-test-modules/modules/500-upmeter/images/webui/werf.inc.yaml
        Module  - upmeter
        Value   - node:14-alpine3.12@sha256:426384fb33a11d27dbbdc545f39bb8daacd3e7db7c60b52cd6bc0597e0045b8d

🐒 [#k8s-resources]
        Message - Container's SecurityContext missing parameter ReadOnlyRootFilesystem
        Object  - kind = DaemonSet ; name = upmeter-agent ; namespace = d8-upmeter ; container = chown-volume-data
        Module  - upmeter