[LLDB] Fix tests that fail when using internal shell.

These tests were failing on darwin, because the internal shell
needs environment var definitions to start with 'env'.  This PR
(hopefully) fixes that problem.

Author: cmtice

lldb/test/Shell/Host/TestCustomShell.test

@@ -6,7 +6,7 @@
 # XFAIL: system-openbsd
 
 # RUN: %clang_host %S/Inputs/simple.c -g -o %t.out
-# RUN: SHELL=bogus not %lldb %t.out -b -o 'process launch -X 1 --' 2>&1 | FileCheck %s --check-prefix ERROR
+# RUN: env SHELL=bogus not %lldb %t.out -b -o 'process launch -X 1 --' 2>&1 | FileCheck %s --check-prefix ERROR
 # RUN: env -i ASAN_OPTIONS='detect_container_overflow=0' %lldb %t.out -b -o 'process launch -X 1 --' 2>&1 | FileCheck %s
 
 # ERROR: error: shell expansion failed

lldb/test/Shell/SymbolFile/DWARF/deterministic-build.cpp

@@ -3,7 +3,7 @@
 // requires the ld64 linker, which clang invokes by default.
 // REQUIRES: system-darwin
 // RUN: %clang_host %s -g -c -o %t.o
-// RUN: ZERO_AR_DATE=1 %clang_host %t.o -g -o %t
+// RUN: env ZERO_AR_DATE=1 %clang_host %t.o -g -o %t
 // RUN: %lldb %t -o "breakpoint set -f %s -l 11" -o run -o exit | FileCheck %s
 // CHECK: stop reason = breakpoint
 

lldb/test/Shell/SymbolFile/add-dsym.test

@@ -4,5 +4,5 @@
 # HELP: Syntax: add-dsym <cmd-options> <filename>
 
 # RUN: yaml2obj %S/Inputs/a.yaml -o %t.out
-# RUN: LLDB_APPLE_DSYMFORUUID_EXECUTABLE=%S/Inputs/dsymforuuid.sh %lldb %t.out -o 'add-dsym -u 41945CA4-5D9D-3CDE-82B4-37E4C09750B5' 2>&1 | FileCheck %s
+# RUN: env LLDB_APPLE_DSYMFORUUID_EXECUTABLE=%S/Inputs/dsymforuuid.sh %lldb %t.out -o 'add-dsym -u 41945CA4-5D9D-3CDE-82B4-37E4C09750B5' 2>&1 | FileCheck %s
 # CHECK: UUID information was not found