feat: use embed for template

[kenny-not-dead]

PR Details

use package embed for template

Description

convenient way to interact with templates

Related Issue

Motivation and Context

Inspired by your library, I'm developing my own, based on your approach, but for processing pptx presentations. When working with templates, I found viewing the base template as a string rather inconvenient. Embed solved this problem.
so I wanted to offer this to you after some time

How Has This Been Tested

go test

Types of changes

• Docs change / refactoring / dependency upgrade
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.60%. Comparing base (f4a068b) to head (51030c8).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #2332   +/-   ##
=======================================
  Coverage   99.60%   99.60%           
=======================================
  Files          32       32           
  Lines       26855    26855           
=======================================
  Hits        26749    26749           
  Misses         55       55           
  Partials       51       51           

Flag	Coverage Δ
unittests	99.60% <ø> (ø)

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[xuri]

Thanks for the PR. Since the new template files use pretty-printing with four space indentation and newlines, it increases the default workbook size and effect file-hash comparisons for users, so I don't think this change is necessary. You can easily introduce new variables in template.go within your own fork.