Feat: Add expect syntax by wrapping assert syntax

[Sorikairox]

Contains the following. Sadly couldn't make time to write tests (life happened).

• expect(value)
• .not
• .resolves
• .rejects
• .toBe(value)
• .toHaveLength(number)
• .toHaveProperty(keyPath, value?)
• .toBeCloseTo(number, numDigits?)
• .toBeDefined()
• .toBeFalsy()
• .toBeGreaterThan(number | bigint)
• .toBeGreaterThanOrEqual(number | bigint)
• .toBeLessThan(number | bigint)
• .toBeLessThanOrEqual(number | bigint)
• .toBeInstanceOf(Class)
• .toBeNull()
• .toBeTruthy()
• .toBeUndefined()
• .toBeNaN()
• .toContain(item)
• .toContainEqual(item)
• .toEqual(value)
• .toMatch(regexp | string)
• .toMatchObject(object)
• .toStrictEqual(value)
• .toThrow(error?)

related #1779

[Sorikairox]

If anyone has any clue on what the following error mean:

Run deno task lint:deprecations
Task lint:deprecations deno run --allow-read --allow-net ./_tools/check_deprecation.ts
Download https://deno.land/x/deno_doc@0.59.0/mod.ts
Download https://deno.land/x/deno_doc@0.59.0/lib/deno_doc.generated.js
Download https://deno.land/x/deno_graph@0.[4](https://github.com/denoland/deno_std/actions/runs/6106288969/job/16571102052?pr=3627#step:7:5)[5](https://github.com/denoland/deno_std/actions/runs/6106288969/job/16571102052?pr=3627#step:7:6).0/lib/loader.ts
error: Uncaught (in promise) Error: ../../assert/assertion_error
      const ret = new Error(getStringFromWasm0(arg0, arg1));
                  ^
    at __wbg_new_15d39[6](https://github.com/denoland/deno_std/actions/runs/6106288969/job/16571102052?pr=3627#step:7:7)6e9981a196 (https://deno.land/x/deno_doc@0.59.0/lib/deno_doc.generated.js:498:19)
    at <anonymous> (https://deno.land/x/deno_doc@0.59.0/lib/deno_doc_bg.wasm:1:2056[7](https://github.com/denoland/deno_std/actions/runs/6106288969/job/16571102052?pr=3627#step:7:8)[8](https://github.com/denoland/deno_std/actions/runs/6106288969/job/16571102052?pr=3627#step:7:9)1)
    at <anonymous> (https://deno.land/x/deno_doc@0.5[9](https://github.com/denoland/deno_std/actions/runs/6106288969/job/16571102052?pr=3627#step:7:10).0/lib/deno_doc_bg.wasm:1:1509332)
    at <anonymous> (https://deno.land/x/deno_doc@0.59.0/lib/deno_doc_bg.wasm:1:1522600)
    at <anonymous> (https://deno.land/x/deno_doc@0.59.0/lib/deno_doc_bg.wasm:1:2008543)
    at __wbg_adapter_46 (https://deno.land/x/deno_doc@0.59.0/lib/deno_doc.generated.js:231:6)
    at real (https://deno.land/x/deno_doc@0.59.0/lib/deno_doc.generated.js:215:14)
    at eventLoopTick (ext:core/01_core.js:183:[11](https://github.com/denoland/deno_std/actions/runs/6106288969/job/16571102052?pr=3627#step:7:12))
Error: Process completed with exit code 1.```

[kt3k]

Let's not export this, but copy it into expect.ts to avoid increasing the public types.

[kt3k]

If anyone has any clue on what the following error mean:

Looks like the error caused by import specifiers without .ts extension. (The error message looks too unfriendly though (Created an issue in deno_doc denoland/deno_doc#348 ))

[iuioiua]

Hi @Sorikairox, is this PR ready to merge or did you need a hand with anything?

[kt3k]

Thanks for working on this @Sorikairox

We'll continue the rest of tasks in other branch!

[kt3k]

We opened #3814 for continuing the work.