Fix footnote

Author: emhane

discv5/discv5-theory.md

@@ -539,7 +539,7 @@ containers, these are abbreviated in the sequence diagram below as follows:
         participant Alice
         participant Relay
         participant Bob
-        
+
         Relay-->>Alice: m(NODES[Bob's ENR])
         Alice->>Bob: m(nonce,FINDNODE)
         Note left of Alice:Hole punched in Alice's NAT for Bob
@@ -554,7 +554,7 @@ As part of a periodic recursive query to fill its kbuckets, Alice sends a FINDNO
 request to Bob, who's ENR it received from Relay. By making an outgoing request to
 Bob, if Alice is behind a NAT, Alice's NAT adds the filtering rule
 `(Alice's-LAN-ip, Alice's-LAN-port, Bob's-WAN-ip, Bob's-WAN-port, entry-lifetime)` to
-it's UDP session table [^1^2]. The request to Bob times out as Bob is behind a NAT.
+it's UDP session table [^1][^2]. The request to Bob times out as Bob is behind a NAT.
 
 
 [EIP-778]: ../enr.md