[bug#46445] [PATCH] tests: Make the STORE test more robust in a "pure" environment.

[Leo Famulari]

Otherwise, the test crashes (not fails) when run in `guix environment --pure 
guix`.

I'm not sure this is the right approach, when I look at commit
3d43017026f9995ad128915db8ca5eafe061bf75, which added this variable.

* tests/store.scm (%shell): Fallback to "/bin/sh".
---
 tests/store.scm | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/store.scm b/tests/store.scm
index cda0e0302f..9c25adf5e9 100644
--- a/tests/store.scm
+++ b/tests/store.scm
@@ -50,7 +50,7 @@
   (open-connection-for-tests))
 
 (define %shell
-  (or (getenv "SHELL") (getenv "CONFIG_SHELL")))
+  (or (getenv "SHELL") (getenv "CONFIG_SHELL") "/bin/sh"))
 
 
 (test-begin "store")
-- 
2.30.0