Remove cargo update from version-bump script (#796)

Looks like `minidump-processor` is now using symbolic as well. And we cannot bump the version
of its symbolic dependency because its an out-of-workspace package. `cargo update` in that case would
require the version to already exist in the registry.

Just remove the `cargo update`. We do not check in our lockfile so whatever updates it would do would never be committed anyway.

scripts/bump-version

@@ -17,4 +17,3 @@ echo "Bumping version: ${NEW_VERSION}"
 TOML_FILES="$(git ls-files '*Cargo.toml')"
 perl -pi -e "s/^version = .*\$/version = \"$NEW_VERSION\"/" $TOML_FILES
 perl -pi -e "s/^(symbolic.*version = )\"[^\"]*\"/\\1\"$NEW_VERSION\"/" $TOML_FILES
-cargo update -p symbolic --precise "${NEW_VERSION}"