Update local testnet doc and parameters (#4749)

* update

* revise link

* update parameters

* update doc

* Update doc

* add quic port

* remove debug log

* Fix el_bootnode not being killed

* Fix time

* Fix doc in manual creation of testnet

* Update file

* update api doc

* Revert "update api doc"

This reverts commit ed695743de.

* add git clone

* Fix path

* Fix path

* Update scripts/local_testnet/setup_time.sh

Co-authored-by: Jimmy Chen <jchen.tc@gmail.com>

* Update scripts/local_testnet/README.md

Co-authored-by: Jimmy Chen <jchen.tc@gmail.com>

* Fix SLOT_PER_EPOCH that changes with mainnet or minimal

* Embedded setup_time.sh in start_local_testnet.sh

* fix slot per epoch constant

* Add comment

* Add CANCUN_TIME

* Fix CANCUN_TIME constant 32 slots

* Correct typo

* chmod +x ./setup_time.sh

---------

Co-authored-by: Jimmy Chen <jchen.tc@gmail.com>

scripts/local_testnet/el_bootnode.sh

@@ -1,3 +1,3 @@
 priv_key="02fd74636e96a8ffac8e7b01b0de8dea94d6bcf4989513b38cf59eb32163ff91"
 source ./vars.env
-$EL_BOOTNODE_BINARY --nodekeyhex $priv_key
+exec $EL_BOOTNODE_BINARY --nodekeyhex $priv_key