🚸 ux(iaas): improve base64 & file flags use + retrocompatibility

[jfbus]

Description

This PR configures all flags used for certificates/keys as file flags.

To ensure a good retrocompatibility, all file flags allow passing the file content as flag value.

Type of Change

Please check the relevant option(s):

• 🐛 Bug fix
• ✨ New feature
• 🧹 Code cleanup or refactor
• 📝 Documentation update
• 🔧 Build or CI-related change
• 🔒 Security fix
• Other (specify): ux

How Has This Been Tested?

Please describe the test strategy:

• Manual testing
• Unit tests
• Integration tests
• Not tested yet

Checklist

• I have followed the Contributing Guidelines
• I have added tests or explained why they are not needed
• I have updated relevant documentation (README, examples, etc.)
• My changes follow the Conventional Commits specification
• My commits include appropriate Gitmoji

Additional Context

[github-actions]

WARNING : Differences in reference doc 🤔

 docs/reference/octl_iaas_api_CreateCa.md                |  2 +-
 docs/reference/octl_iaas_api_CreateServerCertificate.md | 14 +++++++-------
 docs/reference/octl_iaas_ca_create.md                   |  2 +-
 docs/reference/octl_iaas_servercertificate_create.md    |  6 +++---
 4 files changed, 12 insertions(+), 12 deletions(-)

Detailed changes

docs/reference/octl_iaas_api_CreateCa.md

-      --CaPem string         [REQUIRED] The CA in PEM format.
+      --CaPem file           [REQUIRED] The file storing the CA in PEM format.

docs/reference/octl_iaas_api_CreateServerCertificate.md

-      --Body string         [REQUIRED] The PEM-encoded X509 certificate.
-      --Chain string        The PEM-encoded intermediate certification authorities.
+      --Body file         [REQUIRED] The file storing the PEM-encoded X509 certificate.
+      --Chain file        The file storing the PEM-encoded intermediate certification authorities.
-      --PrivateKey string   [REQUIRED] The PEM-encoded private key matching the certificate.
+      --PrivateKey file   [REQUIRED] The file storing the PEM-encoded private key matching the certificate.

docs/reference/octl_iaas_ca_create.md

-      --pem string           [REQUIRED] The CA in PEM format.
+      --pem string           [REQUIRED] The file storing the CA in PEM format.

docs/reference/octl_iaas_servercertificate_create.md

-      --body string          [REQUIRED] The PEM-encoded X509 certificate.
-      --chain string         The PEM-encoded intermediate certification authorities.
+      --body string          [REQUIRED] The file storing the PEM-encoded X509 certificate.
+      --chain string         The file storing the PEM-encoded intermediate certification authorities.
-      --private-key string   [REQUIRED] The PEM-encoded private key matching the certificate.
+      --private-key string   [REQUIRED] The file storing the PEM-encoded private key matching the certificate.

[github-actions]

No flags have changed or have been deleted 😀

[github-actions]

Binary size: 82.3MB => 82.3MB (change +0KB, +0.0%) 😉

[github-actions]

No flags have been deleted 😀