DEV2-4342 fix tabnine.enterprise key

[yonip23]

this line from the CI fails the build:
test "$(cat temp/extension/out/extension.js | grep tabnine.enterprise | wc -l)" = "0"
because I added "tabnine.enterprise" to the non-enterprise plugin in this line:
isSelfHosted: context.workspaceState.get(TABNINE_ENTERPRISE_KEY, false), 🤦🏻

Solution

change the key that's used in the non-enterprise plugin to tabnine.isSelfHosted 🤦🏻

Proof it works

I built the extension locally from this branch and ran the line from the CI:

➜  tabnine-vscode git:(DEV2-4342-fix-release) ✗ test "$(cat temp/extension/out/extension.js | grep tabnine.enterprise | wc -l)" = "0"
➜  tabnine-vscode git:(DEV2-4342-fix-release) ✗ echo $?
0

[amircodota]

LGTM