* Issue #714 Added the fuzzy test.

sumarry:

1. Added a new parameter "fuzzer" to nebula_add_test(cmake).
   Turn on this parameter indicates that the current test is a fuzzy test.
2. Currently only a simple fuzzy test has been added for paser module.
3. The current fuzzy test only supports Clang, so if the compiler was gcc it will skip.

* Move the fuzzer test from the "test" directory to the "fuzzing" directory.

* added the missed cmake file.

* 1. Added a document for fuzz test
2. Added the AFL dictionary for fuzzy test

* Fixed conflict.

* address @dutor's comment.

* Add a new cmake option ENABLE_FUZZ_TEST to control whether to enable the fuzz test.

* Add timeout for storage/meta clients and add some eror logs

* address zlcook's comments

* Added "if not exists" option to create space/tag/edge.

This option allows you to check if the space/tag/edge
that you create already exists in the database.

example:

create space if not exists testspace
create tag if not exists testtag()
create edge if not exists edge1()

* address yixinglu's comments.

Support to create checkpoint for the whole cluster. 
We could use command in console to create/drop/list checkpoints.

To restore from some checkpoint,  users should stop the whole cluster and override data dir with related snapshot dir.  Of course, we will give a tool for that later. 

* Fix possible crash problem in SetExecutor.
Calling Promise::SetValue in onResult would make the memory been deleted while onFinish might been called in another context.

* Fix memory leak in ColumnSpecification.

* implement delete edges

* rebase master

* Support go reversely.

* Save column types.

* Get edges with ranking when travese reversely.

* Address comment.

* Fix input_output in executors.

* Update UT.

* update default configs

* fix ut

* default value

* support default value

* Add geo support.

* Support near function used in from clause.

* Add basic test for geo.

* Add test for geo.

* Modify geo types.

* Rebase and solve conflict.

* Add gflags for geo config.

* Address comment.

* Add cos_similarity function.

* Remove the reserved param in near function.

* support expression in update configs

* fix ut

* Return error of string option

* remove some rocksdb configs, support change more configs in console

* remove change in default template

* fix ut

* update gflags.json

* Fix GitHub Actions failure and upload release asset automatically

Fix compile error in centos6

Add release actions

Fix steps syntax error

Fix tag name error

Test steps outputs in different jobs

Use file to transfer variables between jobs

Use artifacts to share data

Fix upload url

Try to fix appendding url file

Use github api to upload assets

Fix action event

Fix job dependency

Use scripts to upload asset

Refactor vars of outputs between steps

Fix permission denied error

Use upload release asset action

Rename step

Try to fix tag fetch method

Fix upload url

Reuse upload script for node version error in docker container

Cleanup

Fix version var

Fix docker job

* Use sha256sum to compute hash

* Rename SHA EXT

* Upgrade azure docker login action

* Use basename to simplify filename parsing

colse #1232

* Add return sentence.

* Add test.

* Address comment and add more tests.

* Rebase and fix conflict.

* Update.

* balance stop

* address dangleptr's comments

* update log, fix ut

* Implement group by

* Add stdev, bit_and, bit_or, bit_xor

* Rebase upstream

* Address comments and rebase upstream

* rebase master

* Rebase upstream

* Improve the implementation

* Fix yield col not in group cols

* support aggregation in YIELD

* Address CPWstatic and liuyu85cn's comments

close #736

close #930

The crash is caused by the use of two meaningless DCHECK in debug mode.