Suggest explicitly to stripe Python environment squashfs files (#223)

Author: RMeli

docs/guides/gb25.md

@@ -47,14 +47,17 @@ In the first round of GB runs we identified slow job startup times as a common c
 
 With HPE we have identified that the most likely cause is file system contention loading dynamic libraries before `main()` starts.
 
-The fix is to update how the squashfs file for the uenv or container used by your job is stored on the filesystem.
+The fix is to update how the SquashFS file for the uenv or container used by your job is stored on the filesystem.
 
 ```console title="set lustre striping on uenv squashfs file"
 $ uenv image inspect prgenv-gnu/24.11:v2 --format='{sqfs}'
 /capstor/scratch/cscs/bcumming/.uenv-images/images/6068794b820fb4dd91019d020d6d98334a2f9fd23035a5e4a2f72f9dda5f1260/store.squashfs
 $ lfs migrate --stripe-count 20 --stripe-size 1M $(uenv image inspect prgenv-gnu/24.11:v2 --format='{sqfs}')
 ```
 
+If you are using a [SquashFS image for your Python environment][ref-guides-storage-venv],
+you should also set the striping for that file.
+
 As an additional precaution, we recommend to increase the default wait threshold for `MPI_Init` from 180 seconds to 300.
 ```console title="increase MPI initialization time-out"
 $ export PMI_MMAP_SYNC_WAIT_TIME=300