chore: fix LICENSE and NOTICE (#1587)

## Rationale
See https://lists.apache.org/thread/29nyod5d73tn5nov7f5pm0tg42gq57vw

Adhere to https://www.apache.org/legal/src-headers.html

## Detailed Changes


## Test Plan
No need.

chore: fix LICENSE and NOTICE (#1587)

## Rationale
See https://lists.apache.org/thread/29nyod5d73tn5nov7f5pm0tg42gq57vw

Adhere to https://www.apache.org/legal/src-headers.html

## Detailed Changes


## Test Plan
No need.

chore: fix license header (#1579)

## Rationale
Those files should contain asf headers.

## Detailed Changes


## Test Plan
CI

chore: bump version 2.1.0 (#1578)

## Rationale


## Detailed Changes
- Bump version
- Update WAL segment file convention to `seg_{id}`

## Test Plan
CI

chore: remove tini binary (#1503)

## Rationale
Our repo should not contain any binaries.

## Detailed Changes
- Download tini instead of hard copy

## Test Plan
CI

Also I use command below to ensure no other binaries exists.
```
fd -t file --exclude target --exec file {} \; | grep -v ASCII | grep -v UTF-8
```

chore: remove tini binary (#1503)

## Rationale
Our repo should not contain any binaries.

## Detailed Changes
- Download tini instead of hard copy

## Test Plan
CI

Also I use command below to ensure no other binaries exists.
```
fd -t file --exclude target --exec file {} \; | grep -v ASCII | grep -v UTF-8
```

chore: remove tini binary (#1503)

## Rationale
Our repo should not contain any binaries.

## Detailed Changes
- Download tini instead of hard copy

## Test Plan
CI

Also I use command below to ensure no other binaries exists.
```
fd -t file --exclude target --exec file {} \; | grep -v ASCII | grep -v UTF-8
```

chore: add some dependency project descriptions in notice (#1499)

## Rationale
Add some dependency project descriptions in `NOTICE`.

## Detailed Changes
1. Add some dependency project descriptions in `NOTICE`.
2. Add `DEPENDENCIES` file.

## Test Plan
No need.

fix: check ASF header for all source files (#1497)

## Rationale
All source file should have ASF headers.

## Detailed Changes


## Test Plan
CI

chore: add NOTICE file and ASF header (#1491)

## Rationale
Prepare for releasing v2.0.0 .

## Detailed Changes
* Add NOTICE file.
* Add ASF license header.

## Test Plan
CI.