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.

trie/hasher.go

@@ -170,8 +170,8 @@ func (h *hasher) fullnodeToHash(n *fullNode, force bool) node {
 //
 // All node encoding must be done like this:
 //
-//     node.encode(h.encbuf)
-//     enc := h.encodedBytes()
+//	node.encode(h.encbuf)
+//	enc := h.encodedBytes()
 //
 // This convention exists because node.encode can only be inlined/escape-analyzed when
 // called on a concrete receiver type.

trie/proof.go

@@ -339,9 +339,9 @@ findFork:
 // unset removes all internal node references either the left most or right most.
 // It can meet these scenarios:
 //
-// - The given path is existent in the trie, unset the associated nodes with the
-//   specific direction
-// - The given path is non-existent in the trie
+//   - The given path is existent in the trie, unset the associated nodes with the
+//     specific direction
+//   - The given path is non-existent in the trie
 //   - the fork point is a fullnode, the corresponding child pointed by path
 //     is nil, return
 //   - the fork point is a shortnode, the shortnode is included in the range,
@@ -458,15 +458,15 @@ func hasRightElement(node node, key []byte) bool {
 // Expect the normal case, this function can also be used to verify the following
 // range proofs:
 //
-// - All elements proof. In this case the proof can be nil, but the range should
-//   be all the leaves in the trie.
+//   - All elements proof. In this case the proof can be nil, but the range should
+//     be all the leaves in the trie.
 //
-// - One element proof. In this case no matter the edge proof is a non-existent
-//   proof or not, we can always verify the correctness of the proof.
+//   - One element proof. In this case no matter the edge proof is a non-existent
+//     proof or not, we can always verify the correctness of the proof.
 //
-// - Zero element proof. In this case a single non-existent proof is enough to prove.
-//   Besides, if there are still some other leaves available on the right side, then
-//   an error will be returned.
+//   - Zero element proof. In this case a single non-existent proof is enough to prove.
+//     Besides, if there are still some other leaves available on the right side, then
+//     an error will be returned.
 //
 // Except returning the error to indicate the proof is valid or not, the function will
 // also return a flag to indicate whether there exists more accounts/slots in the trie.

trie/stacktrie.go

@@ -375,11 +375,12 @@ func (st *StackTrie) insert(key, value []byte) {
 // hash converts st into a 'hashedNode', if possible. Possible outcomes:
 //
 // 1. The rlp-encoded value was >= 32 bytes:
-//  - Then the 32-byte `hash` will be accessible in `st.val`.
-//  - And the 'st.type' will be 'hashedNode'
+//   - Then the 32-byte `hash` will be accessible in `st.val`.
+//   - And the 'st.type' will be 'hashedNode'
+//
 // 2. The rlp-encoded value was < 32 bytes
-//  - Then the <32 byte rlp-encoded value will be accessible in 'st.val'.
-//  - And the 'st.type' will be 'hashedNode' AGAIN
+//   - Then the <32 byte rlp-encoded value will be accessible in 'st.val'.
+//   - And the 'st.type' will be 'hashedNode' AGAIN
 //
 // This method also sets 'st.type' to hashedNode, and clears 'st.key'.
 func (st *StackTrie) hash() {