[stdlib] Fix `String.split()` and start fixing `String.len()` #236

	# ===----------------------------------------------------------------------=== #
	# Copyright (c) 2024, Modular Inc. All rights reserved.
	#
	# Licensed under the Apache License v2.0 with LLVM Exceptions:
	# https://llvm.org/LICENSE.txt
	#
	# Unless required by applicable law or agreed to in writing, software
	# distributed under the License is distributed on an "AS IS" BASIS,
	# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	# See the License for the specific language governing permissions and
	# limitations under the License.
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	name: Run pre-commit
	on:
	pull_request:
	types: [opened, synchronize, reopened, ready_for_review]
	workflow_dispatch:

	permissions:
	contents: read
	pull-requests: read

	jobs:
	lint:
	runs-on: "ubuntu-latest"
	timeout-minutes: 30

	defaults:
	run:
	shell: bash
	env:
	DEBIAN_FRONTEND: noninteractive

	steps:
	- name: Checkout repo
	uses: actions/checkout@v4

	- name: Download Modular installer
	run: \|
	curl -s https://get.modular.com \| sh -

	- name: Install nightly Mojo compiler
	run: \|
	# The <auth_token> of "examples" is arbitrary but something
	# needs to be provided.
	modular auth examples
	modular install nightly/mojo

	# Put Mojo on the PATH
	echo "MODULAR_HOME=$HOME/.modular" >> $GITHUB_ENV
	echo "$HOME/.modular/pkg/packages.modular.com_nightly_mojo/bin" >> $GITHUB_PATH

	- name: Install pre-commit
	run: \|
	pip install pre-commit
	pre-commit install

	- name: Run pre-commit
	run: pre-commit run --all-files

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