Fix finding composer cache dir (#233)

bin/composer_paths.sh

@@ -46,7 +46,7 @@ if [ ! -f "${composer_lock}" ]; then
 fi
 
 composer_version="$($composer_path --version)"
-cache_dir="$($composer_path config cache-dir)"
+cache_dir="$($composer_path --working-dir="${working_directory}" config cache-dir)"
 
 echo "::debug::Composer path is '${composer_path}'"
 echo "::debug::${composer_version}"

tests/expect/composer_paths_10.exp

@@ -0,0 +1,15 @@
+#!/usr/bin/env -S expect -f
+
+set timeout 3
+# So we don't find a composer.lock in current dir
+cd ..
+spawn ../bin/composer_paths.sh "" "fixtures/with-lock-file"
+match_max 100000
+
+expect "::debug::Composer path is '*'\r
+::debug::Composer version *\r
+::debug::Composer cache directory found at '*composer*'\r
+::debug::File composer.json found at 'fixtures/with-lock-file/composer.json'\r
+::debug::File composer.lock path computed as 'fixtures/with-lock-file/composer.lock'\r
+"
+expect eof