Simplify scripts/run_all.sh

We install `tox` via `pipx` in `Dockerfile`, there is no need to
configure path to `python3.7`.

Also remove use of `pushd`/`popd` and switch from `bash` to `/bin/sh`.

scripts/run_all.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/sh
 #
 # Build the Delta Chat Core Rust library, Python wheels and docs 
 
@@ -8,21 +8,16 @@ set -e -x
 
 # compile core lib
 
-export PATH=/root/.cargo/bin:$PATH
 cargo build --release -p deltachat_ffi
-# cargo test --all --all-features
 
 # Statically link against libdeltachat.a.
-export DCC_RS_DEV=$(pwd)
+export DCC_RS_DEV="$PWD"
 export DCC_RS_TARGET=release
 
-# Configure access to a base python and to several python interpreters
-# needed by tox below.
-export PATH=$PATH:/opt/python/cp37-cp37m/bin
 export PYTHONDONTWRITEBYTECODE=1
+cd python
 
 TOXWORKDIR=.docker-tox
-pushd python
 # prepare a clean tox run
 rm -rf tests/__pycache__
 rm -rf src/deltachat/__pycache__
@@ -37,10 +32,9 @@ unset DCC_NEW_TMP_EMAIL
 # Try to build wheels for a range of interpreters, but don't fail if they are not available.
 # E.g. musllinux_1_1 does not have PyPy interpreters as of 2022-07-10
 tox --workdir "$TOXWORKDIR" -e py37,py38,py39,py310,pypy37,pypy38,pypy39,auditwheels --skip-missing-interpreters true
-popd
 
 
 echo -----------------------
 echo generating python docs
 echo -----------------------
-(cd python && tox --workdir "$TOXWORKDIR" -e doc)
+tox --workdir "$TOXWORKDIR" -e doc