build(deps): Bump tar and @accordproject/template-engine

Bumps [tar](https://github.com/isaacs/node-tar) and [@accordproject/template-engine](https://github.com/accordproject/template-engine). These dependencies needed to be updated together.

Updates `tar` from 6.1.15 to 7.5.12
- [Release notes](https://github.com/isaacs/node-tar/releases)
- [Changelog](https://github.com/isaacs/node-tar/blob/main/CHANGELOG.md)
- [Commits](isaacs/node-tar@v6.1.15...v7.5.12)

Updates `@accordproject/template-engine` from 2.3.4 to 2.8.0
- [Release notes](https://github.com/accordproject/template-engine/releases)
- [Commits](accordproject/template-engine@v2.3.4...v2.8.0)

---
updated-dependencies:
- dependency-name: tar
  dependency-version: 7.5.12
  dependency-type: direct:production
- dependency-name: "@accordproject/template-engine"
  dependency-version: 2.8.0
  dependency-type: direct:production
...

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Author: dependabot[bot]