fix: test_blackwell_kernels.sh script to no longer update dependencies (#1808)

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## 📌 Description

The `scripts/task_test_blackwell_kernels.sh` file for running a series
tests for Blackwell currently reinstalls all dependencies recursively.
This can cause issues with locally configured dependencies being
inadvertently updated (e.g. nvidia-cudnn-cu12==9.13 is installed, but
gets downgraded to nvidia-cudnn-cu12==9.10)

The current PR adds a `--no-deps` flag to keep all dependencies intact
while only installing the FlashInfer build.

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needed. -->

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Author: bkryu

scripts/task_test_blackwell_kernels.sh

@@ -15,7 +15,7 @@ if [[ "$1" == "--dry-run" ]] || [[ "${DRY_RUN}" == "true" ]]; then
 fi
 
 if [ "$DRY_RUN" != "true" ]; then
-    pip install -e . -v
+    pip install -e . -v --no-deps
 fi
 
 EXIT_CODE=0