Remove unnecessary environment variables from workflows. (#18317)

Remove the `IREE_TEST_FILES` and `LD_LIBRARY_PATH` environment variables
from the workflow files as these have been configured on the runner
itself now.

ci-exactly: build_packages,test_amd_mi250,test_amd_mi300,regression_test

Signed-off-by: saienduri <saimanas.enduri@amd.com>
diff --git a/.github/workflows/pkgci_regression_test.yml b/.github/workflows/pkgci_regression_test.yml
index cce6f38..2cc753b 100644
--- a/.github/workflows/pkgci_regression_test.yml
+++ b/.github/workflows/pkgci_regression_test.yml
@@ -133,21 +133,17 @@
           # CPU
           - name: cpu_llvm_task
             models-config-file: models_cpu_llvm_task.json
-            iree-tests-cache: ~/iree_tests_cache
             runs-on: nodai-amdgpu-w7900-x86-64
 
           # AMD GPU
           - name: amdgpu_rocm_mi250_gfx90a
             models-config-file: models_gpu_rocm_gfx90a.json
-            iree-tests-cache: /groups/aig_sharks/iree-tests-cache
             runs-on: nodai-amdgpu-mi250-x86-64
           - name: amdgpu_rocm_mi300_gfx942
             models-config-file: models_gpu_rocm_gfx942.json
-            iree-tests-cache: ~/iree_tests_cache
             runs-on: nodai-amdgpu-mi300-x86-64
           - name: amdgpu_vulkan
             models-config-file: models_gpu_vulkan.json
-            iree-tests-cache: ~/iree_tests_cache
             runs-on: nodai-amdgpu-w7900-x86-64
 
           # NVIDIA GPU
@@ -160,11 +156,9 @@
           # (note: would need to plumb the presubmit/postsubmit runner-group through to here too)
     env:
       PACKAGE_DOWNLOAD_DIR: ${{ github.workspace }}/.packages
-      IREE_TEST_FILES: ${{ matrix.iree-tests-cache }}
       IREE_TEST_PATH_EXTENSION: ${{ github.workspace }}/build_tools/pkgci/external_test_suite
       MODELS_CONFIG_FILE_PATH: build_tools/pkgci/external_test_suite/${{ matrix.models-config-file }}
       VENV_DIR: ${{ github.workspace }}/venv
-      LD_LIBRARY_PATH: /home/esaimana/Python-3.11.9
     steps:
       # TODO(saienduri): Find alternative to this temporary step that manipulates permission of github actions
       # directory to be able to clean after every PR
@@ -240,26 +234,21 @@
           - name: cpu_llvm_task
             models-config-file: models_cpu_llvm_task.json
             backend: cpu
-            iree-tests-cache: ~/iree_tests_cache
             runs-on: nodai-amdgpu-w7900-x86-64
 
           # AMD GPU
           - name: amdgpu_rocm_mi250_gfx90a
             rocm-chip: gfx90a
             backend: rocm
-            iree-tests-cache: /groups/aig_sharks/iree-tests-cache
             runs-on: nodai-amdgpu-mi250-x86-64
           - name: amdgpu_rocm_mi300_gfx942
             rocm-chip: gfx942
             backend: rocm
-            iree-tests-cache: ~/iree_tests_cache
             runs-on: nodai-amdgpu-mi300-x86-64
     env:
       PACKAGE_DOWNLOAD_DIR: ${{ github.workspace }}/.packages
-      IREE_TEST_FILES: ${{ matrix.iree-tests-cache }}
       IREE_TEST_PATH_EXTENSION: ${{ github.workspace }}/build_tools/pkgci/external_test_suite
       VENV_DIR: ${{ github.workspace }}/venv
-      LD_LIBRARY_PATH: /home/esaimana/Python-3.11.9
     steps:
       # TODO(saienduri): Find alternative to this temporary step that manipulates permission of github actions
       # directory to be able to clean after every PR
diff --git a/.github/workflows/pkgci_test_amd_mi300.yml b/.github/workflows/pkgci_test_amd_mi300.yml
index 61fe621..8d301df 100644
--- a/.github/workflows/pkgci_test_amd_mi300.yml
+++ b/.github/workflows/pkgci_test_amd_mi300.yml
@@ -29,7 +29,6 @@
       IREE_CUDA_DISABLE: 1
       IREE_HIP_DISABLE: 0
       IREE_HIP_TEST_TARGET_CHIP: "gfx942"
-      LD_LIBRARY_PATH: /home/esaimana/Python-3.11.9
     steps:
       - name: Pre Checkout MI300 Step
         if: contains(matrix.name, 'gfx942')