Update pull request information in readme

[moninom1]

Description

Update information on how to raise a pull request in readme, so it is readily available for the user.

Test Steps

NA

Checklist:

• [ ] I have tested my changes. No regression in existing tests.
• [ ] I have modified and/or added unit-tests to cover the code changes in this Pull Request.

Related Issue

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[sonarcloud[bot]]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
0.0% Duplication

[codecov[bot]]

Codecov Report

All modified lines are covered by tests :white_check_mark:

Comparison is base (3d575b5) 93.62% compared to head (038d9dc) 93.62%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #821 +/- ## ======================================= Coverage 93.62% 93.62% ======================================= Files 6 6 Lines 2508 2508 Branches 598 598 ======================================= Hits 2348 2348 Misses 107 107 Partials 53 53 ``` | [Flag](https://app.codecov.io/gh/FreeRTOS/FreeRTOS-Kernel/pull/821/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=FreeRTOS) | Coverage Δ | | |---|---|---| | [unittests](https://app.codecov.io/gh/FreeRTOS/FreeRTOS-Kernel/pull/821/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=FreeRTOS) | `93.62% <ø> (ø)` | | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=FreeRTOS#carryforward-flags-in-the-pull-request-comment) to find out more.

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.