Feat/empty blocks

[quertc]

Updated tenderduty with new metrics for empty CL blocks and corresponding notifications in discord/telegram/pagerduty.

New prometheus stats:

• tenderduty_empty_proposed_blocks - count of empty blocks proposed (blocks with zero transactions) since tenderduty was started
• tenderduty_consecutive_empty_blocks - the current count of consecutively proposed empty blocks

Alerts configuration (located in example-config.yml):

# Empty blocks notification configuration
consecutive_empty_enabled: yes
# How many consecutive empty blocks should trigger a notification?
consecutive_empty: 3
# Consecutive Empty alert Pagerduty Severity
consecutive_empty_priority: critical

# For some Cosmos EVM chains, empty consensus blocks may decrease execution uptime
# since they aren't included in EVM state. Should an alert be sent if empty blocks are detected?
empty_percentage_enabled: yes
# What percentage should trigger the alert
empty_percentage: 2
# Percentage Empty alert Pagerduty Severity
empty_percentage_priority: warning

[dylanschultzie]

Thanks! I'm going to pull and test this later today.