Rename revcomp 8 to 9 (#26045)

[reviewed by @jabraham17 ]

For some reason, the CLBG site renamed our revcomp 8 version to 9, so
this updates our version to reflect that and minimize confusion going
forward. That said, there is still the potential for some confusion
because I didn't want to rename all our existing .dat files, nor to lose
historical data, so I'm still using `revcomp8-submitted.dat` as the name
of the data file even though the other files are all named revcomp9.*.
The key in the graph tries to not to this slightly by calling the
version `(9, was 8)`

test/studies/shootout/submitted/revcomp-submitted.graph

@@ -1,5 +1,5 @@
 perfkeys: real, real, real, real
-graphkeys: release, submitted (3), submitted (5), submitted (8)
+graphkeys: release, submitted (3), submitted (5), submitted (9, was 8)
 files: revcomp.dat, revcomp3-submitted.dat, revcomp5-submitted.dat, revcomp8-submitted.dat
 graphtitle: Submitted Reverse-complement Shootout Benchmark
 ylabel: Time (seconds)

test/studies/shootout/submitted/revcomp8.chpl → test/studies/shootout/submitted/revcomp9.chpl

@@ -2,7 +2,7 @@
    https://salsa.debian.org/benchmarksgame-team/benchmarksgame/
 
    contributed by Brad Chamberlain
-   based on the C gcc #8 version by Jeremy Zerfas
+   based on the C gcc #9 version by Jeremy Zerfas
 */
 
 use IO, CTypes;