[llvm-lit] Fix Unhashable TypeError when using lit's internal shell (llvm#101590)

When using the lit internal shell with the command:
```
LIT_USE_INTERNAL_SHELL=1 ninja check-compiler-rt
```
The follow error is encountered:
```
File "TestRunner.py", line 770, in _executeShCmd
    inproc_builtin = inproc_builtins.get(args[0], None)
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
TypeError: unhashable type: 'GlobItem'
```
This error is in a compiler-rt file:
```
TestCases/Linux/long-object-path.cpp
```
This error occurs because `args[0]` is of type `GlobItem`, which is not
hashable, leading to a `TypeError` when it is passed in
`inproc_builtins.get()`. To resolve this issue, I have updated the
implementation to ensure that `args[0]` is hashable before it is used in
`inproc_builtins`.
fixes: llvm#102389
[link to
RFC](https://discourse.llvm.org/t/rfc-enabling-the-lit-internal-shell-by-default/80179)

Author: Harini0924

llvm/utils/lit/lit/TestRunner.py

@@ -767,6 +767,10 @@ def _executeShCmd(cmd, shenv, results, timeoutHelper):
         # echo-appending to a file.
         # FIXME: Standardize on the builtin echo implementation. We can use a
         # temporary file to sidestep blocking pipe write issues.
+
+        # Ensure args[0] is hashable.
+        args[0] = expand_glob(args[0], cmd_shenv.cwd)[0]
+
         inproc_builtin = inproc_builtins.get(args[0], None)
         if inproc_builtin and (args[0] != "echo" or len(cmd.commands) == 1):
             # env calling an in-process builtin is useless, so we take the safe