[docs]: Document build tag for WASM SQLite (#2942)

Follow-up for #2863.

scripts/build.sh

@@ -22,6 +22,7 @@ GO_GCFLAGS=${GO_GCFLAGS-}
 # - noerrcaller: disables caller function prefix in errors                   (slightly better performance, at cost of err readability)
 # - debug:       enables /debug/pprof endpoint                               (adds debug, at performance cost)
 # - debugenv:    enables /debug/pprof endpoint if DEBUG=1 env during runtime (adds debug, at performance cost)
+# - wasmsqlite3: uses SQLite through WASM instead of the C-to-Go transpilation (experimental)
 log_exec env CGO_ENABLED=0 go build -trimpath -v \
                        -tags "${GO_BUILDTAGS}" \
                        -ldflags="${GO_LDFLAGS}" \