fix: ensure observer component name is only set when configurable

[kitsuned]

this patch addresses issue with environments where function name property is not configurable, notably pre-ES2015.

the same condition exists in MobX: core/action.ts.

regarding tests, I couldn't find a feasible way to seal a function, which was also discussed in #2262.

$ podman run --rm node:0.12 node -p 'Object.getOwnPropertyDescriptor(function() {}, "name")'
{ value: '',
  writable: false,
  enumerable: false,
  configurable: false }

$ podman run --rm node:0.12 node -e 'Object.defineProperty(function() {}, "name", { value: "foobar" })'
[eval]:1
Object.defineProperty(function() {}, "name", { value: "foobar" })
       ^
TypeError: Cannot redefine property: name
    at Function.defineProperty (native)
    at [eval]:1:8
    at Object.exports.runInThisContext (vm.js:74:17)
    at Object.<anonymous> ([eval]-wrapper:6:22)
    at Module._compile (module.js:460:26)
    at evalScript (node.js:431:25)
    at startup (node.js:90:7)
    at node.js:814:3

Code change checklist

• Added/updated unit tests
• Updated /docs. For new functionality, at least API.md should be updated
• Verified that there is no significant performance drop (yarn mobx test:performance)

[changeset-bot]

🦋 Changeset detected

Latest commit: b994e02

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
mobx-react-lite	Patch

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[urugator]

LGTM Thank you!