Semicolon Cleanup

1. Semicolons were required in the wrong spot.
2. Make semicolons "invisible" (from the tree-sitter perspective).

Signed-off-by: Will Hawkins <hawkinsw@obs.cr>

tree-sitter-p4/test/corpus/declarations.txt

@@ -31,7 +31,6 @@ parser simple() {
         (identifier)
        )
       )
-      (semicolon)
      )
      (parserTransitionStatement
       (transition)
@@ -39,12 +38,10 @@ parser simple() {
        (identifier)
       )
      )
-     (semicolon)
     )
    )
   )
  )
- (semicolon)
 )
 
 =========================
@@ -80,7 +77,6 @@ parser simple() {
         (identifier)
        )
       )
-      (semicolon)
      )
      (parserTransitionStatement
       (transition)
@@ -88,12 +84,10 @@ parser simple() {
        (identifier)
       )
      )
-     (semicolon)
     )
    )
   )
  )
- (semicolon)
 )
 
 =========================
@@ -129,7 +123,6 @@ parser simple() {
         (identifier)
        )
       )
-      (semicolon)
      )
      (parserTransitionStatement
       (transition)
@@ -137,12 +130,10 @@ parser simple() {
        (identifier)
       )
      )
-     (semicolon)
     )
    )
   )
  )
- (semicolon)
 )
 
 =========================
@@ -182,7 +173,6 @@ parser simple() {
         )
        )
       )
-      (semicolon)
      )
      (parserTransitionStatement
       (transition)
@@ -190,11 +180,9 @@ parser simple() {
        (identifier)
       )
      )
-     (semicolon)
     )
    )
   )
  )
- (semicolon)
 )