Fix deprecations

[michaeladler]

Description

• ioutil is deprecated in Go 1.19, see https://pkg.go.dev/io/[email protected]
• require at least Go 1.19 (1.18 is end-of-life)
• goreleaser rlcp is now the default and can't be changed

Issues Addressed

List and link all the issues addressed by this PR.

Change Type

Please select the relevant options:

• Bug fix (non-breaking change that resolves an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist

• I have read the CONTRIBUTING document.
• My changes adhere to the established code style, patterns, and best practices.
• I have added tests that demonstrate the effectiveness of my changes.
• I have updated the documentation accordingly (if applicable).
• I have added an entry in the CHANGELOG to document my changes (if applicable).

[codecov]

Codecov Report

Merging #37 (9dc0031) into main (ecf9563) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main      #37   +/-   ##
=======================================
  Coverage   77.66%   77.66%           
=======================================
  Files          79       79           
  Lines        3027     3027           
=======================================
  Hits         2351     2351           
  Misses        497      497           
  Partials      179      179