Fix #21169 - Ensure Copy format is plain text

[darkwing]

Description

After doing some research, our usage of copy-to-clipboard uses the default options, one of which is format that defaults to text/html. Since we only want the address copied, we should use the text/plain format.

Manual testing steps

1. Click any "copy to clipboard" button.
2. Ensure the output is plain text and not html

Related issues

Fixes #21169

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[github-actions]

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[vthomas13]

nice find

[garrettbear]

Working for me, looks like some tests just need to quickly be updated

[metamaskbot]

Builds ready [2de8f11]

• builds: chrome, firefox
• builds (beta): chrome
• builds (flask): chrome, firefox
• builds (MMI): chrome, firefox
• builds (test): chrome, firefox
• builds (test-flask): chrome, firefox
• build viz: Build System
• mv3: Background Module Init Stats
• mv3: UI Init Stats
• mv3: Module Load Stats
• mv3: Bundle Size Stats
• mv2: E2e Actions Stats
• code coverage: Report
• storybook: Storybook
• typescript migration: Dashboard
• all artifacts
• bundle viz:

  • background: 0, 1, 2, 3, 4
  • common: 0, 1, 2, 3, 4, 5, 6
  • content-script: 0
  • contentscript: contentscript
  • disable-console: disable-console
  • inpage: inpage
  • policy-load: policy-load
  • sentry-install: sentry-install
  • ui: 0, 1, 10, 11, 12, 13, 2, 3, 4, 5, 6, 7, 8, 9

Page Load Metrics (1366 ± 350 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	88	136	104	14	7
		domContentLoaded	72	136	97	15	7
		load	83	1926	1366	729	350
		domInteractive	72	136	97	15	7

Bundle size diffs

• background: 0 Bytes (0.00%)
• ui: 1.32 KiB (0.02%)
• common: 0 Bytes (0.00%)