build: upgrade to go 1.19 (#25726)

This changes the CI / release builds to use the latest Go version. It also
upgrades golangci-lint to a newer version compatible with Go 1.19.

In Go 1.19, godoc has gained official support for links and lists. The
syntax for code blocks in doc comments has changed and now requires a
leading tab character. gofmt adapts comments to the new syntax
automatically, so there are a lot of comment re-formatting changes in this
PR. We need to apply the new format in order to pass the CI lint stage with
Go 1.19.

With the linter upgrade, I have decided to disable 'gosec' - it produces
too many false-positive warnings. The 'deadcode' and 'varcheck' linters
have also been removed because golangci-lint warns about them being
unmaintained. 'unused' provides similar coverage and we already have it
enabled, so we don't lose much with this change.

core/state/snapshot/generate_test.go

@@ -220,10 +220,12 @@ func (t *testHelper) CommitAndGenerate() (common.Hash, *diskLayer) {
 //   - miss in the beginning
 //   - miss in the middle
 //   - miss in the end
+//
 // - the contract(non-empty storage) has wrong storage slots
 //   - wrong slots in the beginning
 //   - wrong slots in the middle
 //   - wrong slots in the end
+//
 // - the contract(non-empty storage) has extra storage slots
 //   - extra slots in the beginning
 //   - extra slots in the middle

core/state/snapshot/snapshot.go

@@ -179,10 +179,10 @@ type Tree struct {
 // If the memory layers in the journal do not match the disk layer (e.g. there is
 // a gap) or the journal is missing, there are two repair cases:
 //
-// - if the 'recovery' parameter is true, all memory diff-layers will be discarded.
-//   This case happens when the snapshot is 'ahead' of the state trie.
-// - otherwise, the entire snapshot is considered invalid and will be recreated on
-//   a background thread.
+//   - if the 'recovery' parameter is true, all memory diff-layers will be discarded.
+//     This case happens when the snapshot is 'ahead' of the state trie.
+//   - otherwise, the entire snapshot is considered invalid and will be recreated on
+//     a background thread.
 func New(diskdb ethdb.KeyValueStore, triedb *trie.Database, cache int, root common.Hash, async bool, rebuild bool, recovery bool) (*Tree, error) {
 	// Create a new, empty snapshot tree
 	snap := &Tree{