chore: Don't hardcode /bin/bash (#1011)

Bash is not always installed in /bin/bash. Mitigate that by relying on
bash being in PATH.

Author: twz123

Makefile

@@ -2,7 +2,7 @@
 # Image URL to use all building/pushing image targets
 IMG ?= controller:latest
 
-SHELL := /bin/bash -o pipefail
+SHELL := bash -o pipefail
 VERSION_PACKAGE = github.com/replicatedhq/troubleshoot/pkg/version
 VERSION ?=`git describe --tags --dirty`
 DATE=`date -u +"%Y-%m-%dT%H:%M:%SZ"`

scripts/host-preflight-integration-test.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 function say() {
     echo

scripts/initialize-sbom-build.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 set -euo pipefail
 

test/validate-preflight-e2e.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 set -euo pipefail
 

test/validate-support-bundle-e2e.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 set -euo pipefail