fix(plugin): do not call GitHub content API for releases and tags

[knqyf263]

Description

$ trivy plugin install referrer
...
2024-07-31T14:51:48+04:00       FATAL   Fatal error     plugin install error: failed to install the plugin: unable to download the execution file (https://github.com/aquasecurity/trivy-plugin-referrer/releases/download/v0.3.1/trivy_plugin_referrer_0.3.1_macOS-ARM64.tar.gz): failed to download https://github.com/aquasecurity/trivy-plugin-referrer/releases/download/v0.3.1/trivy_plugin_referrer_0.3.1_macOS-ARM64.tar.gz: Get "https://github.com/aquasecurity/trivy-plugin-referrer/releases/download/v0.3.1/trivy_plugin_referrer_0.3.1_macOS-ARM64.tar.gz": failed to round trip: failed to get the file content: GET https://api.github.com/repos/aquasecurity/trivy-plugin-referrer/contents/releases/download/v0.3.1: 404 Not Found []

Related issues

• Close v0.54.0 is not installing plugins #7273

Checklist

• I've read the guidelines for contributing to this repository.
• I've followed the conventions in the PR title.
• I've added tests that prove my fix is effective or that my feature works.
• I've updated the documentation with the relevant information (if needed).
• I've added usage information (if the PR introduces new options)
• I've included a "before" and "after" example to the description (if the PR is a user interface change).

[DmitriyLewen]

These changes work correctly:

➜  ./trivy -d plugin install referrer
2024-07-31T17:07:18+06:00       DEBUG   Cache dir       dir="/Users/dmitriy/Library/Caches/trivy"
2024-07-31T17:07:18+06:00       INFO    [plugin] Installing the plugin...       src="github.com/aquasecurity/trivy-plugin-referrer"
2024-07-31T17:07:20+06:00       DEBUG   [plugin] Loading the plugin metadata...
2024-07-31T17:07:20+06:00       DEBUG   Installing the plugin...        path="/Users/dmitriy/.trivy/plugins/referrer"
2024-07-31T17:07:20+06:00       DEBUG   Platform found  os="darwin" arch="arm64"
2024-07-31T17:07:20+06:00       DEBUG   Downloading the execution file...       uri="https://github.com/aquasecurity/trivy-plugin-referrer/releases/download/v0.3.1/trivy_plugin_referrer_0.3.1_macOS-ARM64.tar.gz"
2024-07-31T17:07:22+06:00       INFO    [plugin] Plugin successfully installed  name="referrer" version="0.3.1"
➜  ./trivy plugin list                 
Installed Plugins:
  Name:    referrer
  Version: 0.3.1

[knqyf263]

@aqua-bot backport release/v0.54

[aqua-bot]

Backport PR created: #7279