Dependabot #2 #3 #4 fixes

[Xemdo]

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

Problem/Feature

Fixes Dependabot alerts:

• https://github.com/twitchdev/twitch-cli/security/dependabot/2
• https://github.com/twitchdev/twitch-cli/security/dependabot/3
• https://github.com/twitchdev/twitch-cli/security/dependabot/4

Description of Changes:

• Updated versions for golang.org/x/text and golang.org/x/sys
• Updated Go version to 1.18

Checklist

• My code follows the Contribution Guide
• I have self-reviewed the changes being requested
• I have made comments on pieces of code that may be difficult to understand for other editors
• I have updated the documentation (if applicable)

[Xemdo]

Tests are a bit weird because it's including the original tests as well. Those will most definitely fail, but pull requests in the future shouldn't have this issue.