Rename gfork to gingerbread

[palango]

Description

• Give the hardfork it's proper name
• Adapt the override.espresso flag to gingerbread

[github-actions]

Coverage from tests in ./e2e_test/... for ./consensus/istanbul/... at commit 0fbd1f2

coverage: 49.2% of statements across all listed packages

coverage:  60.0% of statements in consensus/istanbul
coverage:  40.1% of statements in consensus/istanbul/announce
coverage:  54.5% of statements in consensus/istanbul/backend
coverage:   0.0% of statements in consensus/istanbul/backend/backendtest
coverage:  24.3% of statements in consensus/istanbul/backend/internal/replica
coverage:  63.5% of statements in consensus/istanbul/core
coverage:  45.0% of statements in consensus/istanbul/db
coverage:   0.0% of statements in consensus/istanbul/proxy
coverage:  64.4% of statements in consensus/istanbul/uptime
coverage:  51.8% of statements in consensus/istanbul/validator
coverage:  79.2% of statements in consensus/istanbul/validator/random

[github-actions]

[codecov]

Codecov Report

Patch coverage: 64.80% and project coverage change: +1.06 🎉

Comparison is base (71bdbcf) 54.30% compared to head (a148e25) 55.36%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2127      +/-   ##
==========================================
+ Coverage   54.30%   55.36%   +1.06%     
==========================================
  Files         692      675      -17     
  Lines      115642   113665    -1977     
==========================================
+ Hits        62795    62927     +132     
+ Misses      49014    46911    -2103     
+ Partials     3833     3827       -6     

Impacted Files	Coverage Δ
cmd/devp2p/internal/ethtest/transaction.go	0.00% <0.00%> (ø)
cmd/geth/chaincmd.go	0.00% <0.00%> (ø)
cmd/geth/config.go	0.00% <0.00%> (ø)
cmd/geth/main.go	21.39% <ø> (+0.91%)	⬆️
cmd/geth/usage.go	10.90% <ø> (ø)
cmd/utils/flags.go	2.56% <0.00%> (ø)
consensus/istanbul/utils.go	47.10% <ø> (+1.13%)	⬆️
contracts/currency/currency.go	55.00% <ø> (ø)
contracts/election/election.go	25.00% <ø> (ø)
contracts/epoch_rewards/epoch_rewards.go	88.88% <ø> (ø)
... and 56 more

... and 35 files with indirect coverage changes

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[karlb]

I am not sure how the overrides are used, so I can't judge if the override should be switched from espresso to gingerbread. Apart from that, it looks good!

[palango]

Failing tests will pass once #2130 is merged.