Remove file existence check for Mac environment variables

Signed-off-by: Dom Rodriguez <shymega@shymega.org.uk>

Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "barrier"
+version = "0.1.0"
+edition = "2021"
+publish = false
+
+[dependencies]

clean_build.sh

@@ -24,7 +24,7 @@ B_CMAKE_FLAGS="-DCMAKE_BUILD_TYPE=${B_BUILD_TYPE} ${B_CMAKE_FLAGS:-}"
 
 if [ "$(uname)" = "Darwin" ]; then
     # macOS needs a little help, so we source this environment script to fix paths.
-   [ -e "./macos_environment.sh" ] && . ./macos_environment.sh
+    . ./macos_environment.sh
 
     B_CMAKE_FLAGS="${B_CMAKE_FLAGS} -DCMAKE_OSX_SYSROOT=$(xcode-select --print-path)/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk -DCMAKE_OSX_DEPLOYMENT_TARGET=10.9"
 fi