fix(all): use proper undefined check when using Haptics plugin

[liamdebeasi]

Pull request checklist

Please check if your PR fulfills the following requirements:

• Tests for the changes have been added (for bug fixes / features)
• Docs have been reviewed and added / updated if needed (for bug fixes / features)
• Build (npm run build) was run locally and any changes were pushed
• Lint (npm run lint) has passed locally and any fixes were made for failures

Pull request type

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

What is the current behavior?

Issue Number: #21148

What is the new behavior?

• Add proper check to see if plugin is supported or not

Does this introduce a breaking change?

• Yes
• No

Other information

[liamdebeasi]

Merging this in for 5.1.0 rather than 5.1.1 because I feel this is a high priority fix. (anyone using refresher + capacitor will likely run into this issue when developing)