Fix error when path to Xcode contains a space

[jszumski]

Fixes a truncated DEVELOPER_DIR by quoting the path in case it has spaces like "/Applications/Xcode 26b2.app". Tools invoked from the inner output base will use the truncated value like this rules_swift_package_manager call:

INFO: Repository rules_swift_package_manager++swift_deps+swiftpkg_knit instantiated at:
  <builtin>: in <toplevel>
Repository rule swift_package defined at:
  /private/var/tmp/_bazel_jszumski/ed7e7efa198ffcfaf8285220a74bc6f4/rules_xcodeproj.noindex/build_output_base/external/rules_swift_package_manager+/swiftpkg/internal/swift_package.bzl:226:32: in <toplevel>
ERROR: /private/var/tmp/_bazel_jszumski/ed7e7efa198ffcfaf8285220a74bc6f4/rules_xcodeproj.noindex/build_output_base/external/rules_swift_package_manager+/swiftpkg/internal/repository_utils.bzl:68:13: An error occurred during the fetch of repository 'rules_swift_package_manager++swift_deps+swiftpkg_knit':
   Traceback (most recent call last):
	File "/private/var/tmp/_bazel_jszumski/ed7e7efa198ffcfaf8285220a74bc6f4/rules_xcodeproj.noindex/build_output_base/external/rules_swift_package_manager+/swiftpkg/internal/swift_package.bzl", line 53, column 33, in _swift_package_impl
		repo_rules.check_spm_version(repository_ctx, env = env)
	File "/private/var/tmp/_bazel_jszumski/ed7e7efa198ffcfaf8285220a74bc6f4/rules_xcodeproj.noindex/build_output_base/external/rules_swift_package_manager+/swiftpkg/internal/repo_rules.bzl", line 74, column 31, in _check_spm_version
		spm_ver = spm_versions.get(repository_ctx, env = env)
	File "/private/var/tmp/_bazel_jszumski/ed7e7efa198ffcfaf8285220a74bc6f4/rules_xcodeproj.noindex/build_output_base/external/rules_swift_package_manager+/swiftpkg/internal/spm_versions.bzl", line 39, column 49, in _get_version
		exec_out = repository_utils.exec_spm_command(
	File "/private/var/tmp/_bazel_jszumski/ed7e7efa198ffcfaf8285220a74bc6f4/rules_xcodeproj.noindex/build_output_base/external/rules_swift_package_manager+/swiftpkg/internal/repository_utils.bzl", line 68, column 13, in _execute_spm_command
		fail(err_msg_tpl.format(
Error in fail: Failed to execute SPM command. working_directory: , args: ["xcrun", "swift", "package", "--version"], return_code: 1
xcrun: error: missing DEVELOPER_DIR path: /Applications/Xcode