Update bundler requirement from ~> 1.3 to >= 1.3, < 3.0

Updates the requirements on [bundler](https://github.com/bundler/bundler) to permit the latest version.
- [Release notes](https://github.com/bundler/bundler/releases)
- [Changelog](https://github.com/bundler/bundler/blob/v2.0.1/CHANGELOG.md)
- [Commits](https://github.com/bundler/bundler/commits/v2.0.1)

Signed-off-by: dependabot[bot] <support@dependabot.com>

tdiary.gemspec

@@ -43,5 +43,5 @@ Gem::Specification.new do |spec|
   spec.add_dependency 'rake'
   spec.add_dependency 'sprockets'
   spec.add_dependency 'thor'
-  spec.add_dependency "bundler", "~> 1.3"
+  spec.add_dependency "bundler", ">= 1.3", "< 3.0"
 end