Bump sdk-registry plugin to 1.5.6 (internal-11304)

Bumps `com.mapbox.gradle.plugins:sdk-registry` from `1.5.5` → `1.5.6`
across all Android projects.

## Files changed

| File | Project(s) using it |
|------|---------------------|
| `projects/common/platform/android/gradle/libs.versions.toml` | common,
navigation-native, navigation-sdk-cpp, search-native |
| `projects/maps-android/mapbox-maps-android/gradle/libs.versions.toml`
| maps-android |
| `projects/gl-native/platform/android/gradle/versions.gradle.kts` |
gl-native |
|
`projects/search-android/mapbox-search-android/MapboxSearch/gradle/versions.gradle`
| search-android |
|
`projects/maps-android/vendor/mapbox-gestures-android/gradle/libs.versions.toml`
| maps-android (vendor: mapbox-gestures-android) |
|
`projects/maps-android/vendor/mapbox-polylabel-kotlin/gradle/libs.versions.toml`
| maps-android (vendor: mapbox-polylabel-kotlin) |
| `projects/maps-cpp/platform/android/gradle/libs.versions.toml` |
maps-cpp |

## What's in 1.5.6

Fixes SBOM project packages for `dash-native` and
`search-android-native` recording `4.0.2` (the CMake tool version)
instead of the correct Maven publication snapshot version. The identity
marker written by `ProjectsEvaluatedBuildListener` is now always
preferred over `project.version` when present.

Also reduces config-phase log noise: per-publication SBOM marker logs
are downgraded to `info`, with a single summary line shown on every
sync:
```
[sdk-registry] Configuring upload tasks and SBOM markers (config phase) — run with --info to see details
```

See mapbox/mapbox-android-gradle-plugins#133 for details.

cc @mapbox/search-sdk-android
cc @mapbox/gl-native
cc @mapbox/core-sdk
cc @mapbox/maps-android

cc @mapbox/nav-core-sdk

cc @mapbox/sdk-platform

GitOrigin-RevId: 0330ba49412e433f5fe51f35094f4e5b8a125ad3

Author: pengdev

gradle/libs.versions.toml

@@ -17,7 +17,7 @@ robolectric = "4.14"
 espresso = "3.4.0"
 
 mapboxMaps = "10.16.2"
-sdkRegistry = "1.4.3"
+sdkRegistry = "1.5.6"
 
 [libraries]
 mapbox-maps = { group = "com.mapbox.maps", name = "android", version.ref = "mapboxMaps" }