Avoid unexpected shell expansion

[shikanime]

Some variables may contain symbols such as wildcards, which can be expanded by other shell interpreters such as ZSH.

Fix: #569

[shikanime]

@microsoft-github-policy-service agree

[samruddhikhandale]

Looks great, thanks for taking the time to contribute this PR.
Left a minor comment.

[samruddhikhandale]

ERROR: failed to solve: failed to register layer: ApplyLayer exit status 1 stdout: stderr: write /usr/local/bin/git: no space left on device

Looks like the tests are failing due to ^ disk space issues , see https://github.com/devcontainers/features/actions/runs/5813161318/job/15762628752?pr=645#step:4:3293

@shikanime can you help remove the "install_node_on_universal_image" scenario?

features/test/node/scenarios.json

Lines 40 to 48 in 5128a41

	"install_node_on_universal_image": {
	"image": "mcr.microsoft.com/devcontainers/universal",
	"remoteUser": "codespace",
	"features": {
	"node": {
	"version": "19.1.0"
	}
	}
	},

The universal image is ~ 12.5 GB, we shouldn't be using such a big image which will result in slow (local) test runs. Also, it would help fix the disk space issue in the runners.

I'll create an issue for myself to re-add a (slim) test scenario as a replacement.

[samruddhikhandale]

Opened #646

[samruddhikhandale]

Looks great, thanks!