Add RSA encryption function to templates

[LinuxSuRen]

Related to #501

Adds the rasEncryptWithPublicKey function to the template rendering functionalities and includes unit tests for the new function.

• New Functionality: Implements the rasEncryptWithPublicKey function in pkg/render/template.go, allowing users to encrypt content with a public key directly within templates. This function takes two string arguments (content and key), performs RSA encryption, and returns the encrypted content in base64 encoded format.
• Error Handling: Adds error handling for key parsing and encryption processes within the rasEncryptWithPublicKey function to ensure robustness.
• Unit Tests: Extends pkg/render/template_test.go with tests for the rasEncryptWithPublicKey function, verifying its behavior with both valid and invalid keys, and ensuring the encryption process works as expected.

---

For more details, open the Copilot Workspace session.

[sonarcloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[codacy-production[bot]]

Coverage summary from Codacy

See diff coverage on Codacy

Coverage variation	Diff coverage
:white_check_mark: -0.02%	:white_check_mark: 60.00%

Coverage variation details

| | Coverable lines | Covered lines | Coverage | | ------------- | ------------- | ------------- | ------------- | | Common ancestor commit (b7926da2c0a6a0d0ca94335aec4475771c0fd522) | 15067 | 6496 | 43.11% | | | Head commit (14443d2aaaae5c7a5d0da6221d454751047c1fce) | 15086 (+19) | 6501 (+5) | 43.09% (**-0.02%**) | **Coverage variation** is the difference between the coverage for the head and common ancestor commits of the pull request branch: ` - `

Diff coverage details

| | Coverable lines | Covered lines | Diff coverage | | ------------- | ------------- | ------------- | ------------- | | Pull request (#502) | 20 | 12 | **60.00%** | **Diff coverage** is the percentage of lines that are covered by tests out of the coverable lines that the pull request added or modified: `/ * 100%`

See your quality gate settings    Change summary preferences

---

_{:rocket: Don’t miss a bit, follow what’s new on Codacy.}

_{Codacy stopped sending the deprecated coverage status on June 5th, 2024. Learn more}

[github-actions[bot]]

There are 1 test cases, failed count 0:

Name	Average	Max	Min	Count	Error
	9.383516ms	11.376308ms	8.331835ms	3	0

Reported by api-testing.