feat(decimal): align component with fusion DS - FE-7146

[DipperTheDan]

Proposed behaviour

Updates Decimal to be inline with that of the Fusion DS.

• Add suffix prop
• Add PopoverContainer support
• Add PopoverPosition support

Current behaviour

Decimal is out of date with Fusion DS

Checklist

• Commits follow our style guide
• Related issues linked in commit messages if required
• Screenshots are included in the PR if useful
• All themes are supported if required
• Unit tests added or updated if required
• Playwright automation tests added or updated if required
• Storybook added or updated if required
• Translations added or updated (including creating or amending translation keys table in storybook) if required
• Typescript d.ts file added or updated if required
• Related docs have been updated if required

QA

• Tested in provided StackBlitz sandbox/Storybook
• Add new Playwright test coverage if required
• Carbon implementation matches Design System/designs
• UI Tests GitHub check reviewed if required

Additional context

N/A

Testing instructions

• Component should match designs on the associated ticket.
• No functional regressions should occur due to this work.

[DipperTheDan]

I have had to change this code as when the Decimal component had PopoverContainerContent that included a Select, clicking on the Select textbox focused the Decimal input.