[chore](ut) fix run be ut build script (#49765)

### What problem does this PR solve?

Issue Number: close #xxx

Related PR: #xxx

Problem Summary:

### Release note

None

### Check List (For Author)

- Test <!-- At least one of them must be included. -->
    - [ ] Regression test
    - [ ] Unit Test
    - [ ] Manual test (add detailed scripts or steps below)
    - [ ] No need to test or manual test. Explain why:
- [ ] This is a refactor/code format and no logic has been changed.
        - [ ] Previous test can cover this change.
        - [ ] No code files have been changed.
        - [ ] Other reason <!-- Add your reason?  -->

- Behavior changed:
    - [ ] No.
    - [ ] Yes. <!-- Explain the behavior change -->

- Does this need documentation?
    - [ ] No.
- [ ] Yes. <!-- Add document PR link here. eg:
https://github.com/apache/doris-website/pull/1214 -->

### Check List (For Reviewer who merge this PR)

- [ ] Confirm the release note
- [ ] Confirm test cases
- [ ] Confirm document
- [ ] Add branch pick label <!-- Add branch pick label that this PR
should merge into -->

run-be-ut.sh

@@ -213,6 +213,10 @@ if [[ -z "${USE_DWARF}" ]]; then
     USE_DWARF='OFF'
 fi
 
+if [[ -z "${USE_AVX2}" ]]; then
+    USE_AVX2='ON'
+fi
+
 if [[ -z "${USE_UNWIND}" ]]; then
     if [[ "$(uname -s)" != 'Darwin' ]]; then
         USE_UNWIND='ON'
@@ -246,6 +250,7 @@ cd "${CMAKE_BUILD_DIR}"
     -DUSE_UNWIND="${USE_UNWIND}" \
     -DUSE_MEM_TRACKER="${USE_MEM_TRACKER}" \
     -DUSE_JEMALLOC=OFF \
+    -DUSE_AVX2="${USE_AVX2}" \
     -DEXTRA_CXX_FLAGS="${EXTRA_CXX_FLAGS}" \
     -DENABLE_CLANG_COVERAGE="${DENABLE_CLANG_COVERAGE}" \
     ${CMAKE_USE_CCACHE:+${CMAKE_USE_CCACHE}} \