ci(p4): Change default revision for P4

[lucasssvaz]

Description of Change

This pull request updates the configuration for the ESP32-P4 board to explicitly specify the ChipVariant=postv3 option in all build scripts, documentation, and CI configuration files. This ensures that builds for ESP32-P4 target the correct chip variant and are consistent across the project.

Build and configuration updates:

• Updated the ESP32-P4 build options in .github/scripts/sketch_utils.sh to include ChipVariant=postv3, ensuring the correct chip variant is set during sketch builds.

Documentation updates:

• Modified the list of default FQBNs in docs/en/contributing.rst to show ChipVariant=postv3 for ESP32-P4, reflecting the new standard configuration.

CI configuration updates:

• Updated the ESP32-P4 FQBNs in libraries/ESP_SR/examples/Basic/ci.yml to include ChipVariant=postv3 for all build variants.
• Updated the ESP32-P4 FQBNs in tests/validation/nvs/ci.yml to include ChipVariant=postv3 for all build variants, ensuring consistency in validation tests.

Test Scenarios

CI

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Test Results

  167 files    167 suites   1h 6m 11s ⏱️
   60 tests    59 ✅ 0 💤 1 ❌
1 238 runs  1 231 ✅ 0 💤 7 ❌

For more details on these failures, see this check.

Results for commit f6c2eb8.

♻️ This comment has been updated with latest results.

[github-actions]

Memory usage test (comparing PR against master branch)

The table below shows the summary of memory usage change (decrease - increase) in bytes and percentage for each target.

Memory	FLASH [bytes]		FLASH [%]		RAM [bytes]		RAM [%]
Target	DEC	INC	DEC	INC	DEC	INC	DEC	INC
ESP32C5	0	0	0.00	0.00	0	0	0.00	0.00
ESP32P4	0	⚠️ +446	0.00	⚠️ +0.06	0	⚠️ +64	0.00	⚠️ +0.20
ESP32S3	0	0	0.00	0.00	0	0	0.00	0.00
ESP32S2	0	0	0.00	0.00	0	0	0.00	0.00
ESP32C3	0	0	0.00	0.00	0	0	0.00	0.00
ESP32C6	0	0	0.00	0.00	0	0	0.00	0.00
ESP32H2	0	0	0.00	0.00	0	0	0.00	0.00
ESP32	0	0	0.00	0.00	0	0	0.00	0.00

Click to expand the detailed deltas report [usage change in BYTES]

Target	ESP32C5		ESP32P4		ESP32S3		ESP32S2		ESP32C3		ESP32C6		ESP32H2		ESP32
Example	FLASH	RAM	FLASH	RAM	FLASH	RAM	FLASH	RAM	FLASH	RAM	FLASH	RAM	FLASH	RAM	FLASH	RAM
libraries/BLE/examples/Server	0	0	⚠️ +446	⚠️ +64	0	0	-	-	0	0	0	0	0	0	0	0
libraries/Insights/examples/MinimalDiagnostics	0	0	-	-	0	0	0	0	0	0	0	0	-	-	0	0
libraries/NetworkClientSecure/examples/WiFiClientSecure	0	0	⚠️ +398	0	0	0	0	0	0	0	0	0	-	-	0	0
libraries/ESP_SR/examples/Basic	-	-	⚠️ +322	0	0	0	-	-	-	-	-	-	-	-	-	-
libraries/ESP32/examples/Camera/CameraWebServer	-	-	-	-	0	0	0	0	-	-	-	-	-	-	0	0
ESP32/examples/Camera/CameraWebServer (2)	-	-	-	-	0	0	0	0	-	-	-	-	-	-	0	0
ESP32/examples/Camera/CameraWebServer (3)	-	-	-	-	0	0	-	-	-	-	-	-	-	-	-	-