Remove Impeller/OpenGLES from CI branch for Android e2e tests. (#51734)

We don't intend to make much progress on the Impeller OpenGLES backend in 2024. I won't remove the capability to run these tests locally (the plumbing is already done and doesn't cost anything), but we don't need to have these just sit/flake on CI consuming resources.

Partial work towards flutter/flutter#144064.

Author: matanlurey

.ci.yaml

@@ -89,28 +89,6 @@ targets:
       - testing/scenario_app/**
       - testing/skia_gold_client/**
 
-  # TODO(matanlurey): OpenGLES is very flaky, https://github.com/flutter/flutter/issues/143626.
-  - name: Linux linux_android_emulator_opengles_tests
-    bringup: true
-    enabled_branches:
-      - main
-    recipe: engine_v2/engine_v2
-    properties:
-      config_name: linux_android_emulator_opengles
-      dependencies: >-
-        [
-          {"dependency": "goldctl", "version": "git_revision:720a542f6fe4f92922c3b8f0fdcc4d2ac6bb83cd"}
-        ]
-    timeout: 90
-    runIf:
-      - .ci.yaml
-      - ci/builders/linux_android_emulator.json
-      - DEPS
-      - lib/ui/**
-      - shell/platform/android/**
-      - testing/scenario_app/**
-      - testing/skia_gold_client/**
-
 # Task to run Linux linux_android_emulator_tests on AVDs running Android 33
 # instead of 34 for investigating https://github.com/flutter/flutter/issues/137947.
   - name: Linux linux_android_emulator_tests_api_33