Add configuration diff tool. (#8298)

* Add diff outputs as testdata.
* Normalize all samples to kebabs.

scripts/confix/testdata/diff-31-32.txt

@@ -0,0 +1,5 @@
++S fastsync
++M fastsync.version
++M mempool.max-tx-bytes
++M rpc.max-body-bytes
++M rpc.max-header-bytes

scripts/confix/testdata/diff-32-33.txt

@@ -0,0 +1,6 @@
++M p2p.persistent-peers-max-dial-period
++M p2p.unconditional-peer-ids
++M tx-index.index-all-keys
+-M tx-index.index-all-tags
++M tx-index.index-keys
+-M tx-index.index-tags

scripts/confix/testdata/diff-33-34.txt

@@ -0,0 +1,20 @@
+-M prof-laddr
++M consensus.double-sign-check-height
++M mempool.keep-invalid-txs-in-cache
++M mempool.max-batch-bytes
++M rpc.experimental-close-on-slow-client
++M rpc.experimental-subscription-buffer-size
++M rpc.experimental-websocket-write-buffer-size
++M rpc.pprof-laddr
++S statesync
++M statesync.enable
++M statesync.rpc-servers
++M statesync.trust-height
++M statesync.trust-hash
++M statesync.trust-period
++M statesync.discovery-time
++M statesync.temp-dir
++M statesync.chunk-request-timeout
++M statesync.chunk-fetchers
+-M tx-index.index-all-keys
+-M tx-index.index-keys

scripts/confix/testdata/diff-34-35.txt

@@ -0,0 +1,31 @@
+-M fast-sync
++M mode
+-M priv-validator-key-file
+-M priv-validator-laddr
+-M priv-validator-state-file
++S blocksync
++M blocksync.enable
++M blocksync.version
+-S fastsync
+-M fastsync.version
++M mempool.ttl-duration
++M mempool.ttl-num-blocks
++M mempool.version
+-M mempool.wal-dir
++M p2p.bootstrap-peers
++M p2p.max-connections
++M p2p.max-incoming-connection-attempts
++M p2p.queue-type
+-M p2p.seed-mode
++M p2p.use-legacy
++S priv-validator
++M priv-validator.key-file
++M priv-validator.state-file
++M priv-validator.laddr
++M priv-validator.client-certificate-file
++M priv-validator.client-key-file
++M priv-validator.root-ca-file
+-M statesync.chunk-fetchers
++M statesync.fetchers
++M statesync.use-p2p
++M tx-index.psql-conn

scripts/confix/testdata/diff-35-36.txt

@@ -0,0 +1,27 @@
+-S blocksync
+-M blocksync.enable
+-M blocksync.version
+-M consensus.skip-timeout-commit
+-M consensus.timeout-commit
+-M consensus.timeout-precommit
+-M consensus.timeout-precommit-delta
+-M consensus.timeout-prevote
+-M consensus.timeout-prevote-delta
+-M consensus.timeout-propose
+-M consensus.timeout-propose-delta
+-M mempool.version
+-M p2p.addr-book-file
+-M p2p.addr-book-strict
+-M p2p.max-num-inbound-peers
+-M p2p.max-num-outbound-peers
+-M p2p.persistent-peers-max-dial-period
+-M p2p.unconditional-peer-ids
+-M p2p.use-legacy
++M rpc.event-log-max-items
++M rpc.event-log-window-size
+-M rpc.experimental-close-on-slow-client
++M rpc.experimental-disable-websocket
+-M rpc.experimental-subscription-buffer-size
+-M rpc.experimental-websocket-write-buffer-size
+-M rpc.grpc-laddr
+-M rpc.grpc-max-open-connections