fix: updated message string in onboarding screen

[NidhiKJha]

This PR is to update the onboarding screen message with proper punctuation

Related issues

Fixes: #26763

Manual testing steps

1. Go to onboarding
2. Check the message has proper punctuation on this screen

Screenshots/Recordings

Before

After

Pre-merge author checklist

• I've followed MetaMask Contributor Docs and MetaMask Extension Coding Standards.
• I've completed the PR template to the best of my ability
• I’ve included tests if applicable
• I’ve documented my code using JSDoc format if applicable
• I’ve applied the right labels on the PR (see labeling guidelines). Not required for external contributors.

Pre-merge reviewer checklist

• I've manually tested the PR (e.g. pull and build branch, run the app, test code being changed).
• I confirm that this PR addresses all acceptance criteria described in the ticket it closes and includes the necessary testing evidence such as recordings and or screenshots.

[DDDDDanica]

LGTM ! Added a comment in original ticket for a NIT improvement, we can wait for content designer Corey's response on that one 🙏🏻

[metamaskbot]

Builds ready [6e7a975]

• 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, 5, 6
  • common: 0, 1, 10, 11, 12, 2, 3, 4, 5, 6, 7, 8, 9
  • content-script: 0
  • offscreen: 0
  • ui: 0, 1, 10, 11, 12, 2, 3, 4, 5, 6, 7, 8, 9

Page Load Metrics (1605 ± 74 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	221	1970	1524	331	159
		domContentLoaded	1399	1940	1581	138	66
		load	1418	2022	1605	154	74
		domInteractive	24	163	39	31	15
		backgroundConnect	9	82	27	24	12
		firstReactRender	16	82	38	24	11
		getState	4	47	10	10	5
		initialActions	0	1	0	0	0
		loadScripts	989	1439	1163	111	53
		setupStore	6	59	16	17	8
		uiStartup	1581	2254	1823	174	84

Bundle size diffs [🚨 Warning! Bundle size has increased!]

• background: 0 Bytes (0.00%)
• ui: 0 Bytes (0.00%)
• common: 1 Bytes (0.00%)

[georgewrmarshall]

LGTM! 🚀
I didn't realize we used the oxford comma but sure enough it's a ticket written by Sally and it's in our content guidelines! TIL

[metamaskbot]

Builds ready [ebd5bb2]

• 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, 5, 6
  • common: 0, 1, 10, 11, 12, 2, 3, 4, 5, 6, 7, 8, 9
  • content-script: 0
  • offscreen: 0
  • ui: 0, 1, 10, 11, 12, 2, 3, 4, 5, 6, 7, 8, 9

Page Load Metrics (1670 ± 61 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	1501	2072	1680	132	63
		domContentLoaded	1489	2058	1648	127	61
		load	1502	2073	1670	128	61
		domInteractive	20	100	40	22	11
		backgroundConnect	9	53	25	14	7
		firstReactRender	16	89	37	27	13
		getState	4	71	17	21	10
		initialActions	0	1	0	0	0
		loadScripts	1090	1642	1241	116	55
		setupStore	6	11	7	1	1
		uiStartup	1698	2315	1882	138	66

Bundle size diffs [🚨 Warning! Bundle size has increased!]

• background: 0 Bytes (0.00%)
• ui: 0 Bytes (0.00%)
• common: 1 Bytes (0.00%)