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##### SUMMARY
https://github.com/ansible/ansible/blob/devel/lib/ansible/modules/cloud/misc/terraform.py#L353 expects the plan_file to be a filename not a path to a file.inside of project_path. Works with relative paths but not with absolute paths. Lucky for me I use a path inside project_path but it worked before with paths outside too.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->
terraform
##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.8.1
  config file = /home/adam/.ansible.cfg
  configured module search path = ['/home/adam/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /home/adam/.local/lib/python3.6/site-packages/ansible
  executable location = /home/adam/.local/bin/ansible
  python version = 3.6.8 (default, Jan 14 2019, 11:02:34) [GCC 8.0.1 20180414 (experimental) [trunk revision 259383]]
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below

```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. target OS versions, network device firmware, etc. -->


##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->

<!--- Paste example playbooks or commands between quotes below -->
```yaml
use absolute path for plan_file 
```

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##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->
uses the filepath provided

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->

<!--- Paste verbatim command output between quotes -->
```paste below
TASK [run terraform apply] ***************************************************************************************************************************************************************************************************************************************************************
fatal: [localhost]: FAILED! => {"changed": false, "msg": "Could not find plan_file \"/home/.../plan.tfplan\", check the path and try again."}
```

project_path = module.params.get('project_path')
    bin_path = module.params.get('binary_path')
    workspace = module.params.get('workspace')
    purge_workspace = module.params.get('purge_workspace')
    state = module.params.get('state')
    variables = module.params.get('variables') or {}
    variables_file = module.params.get('variables_file')
    plan_file = module.params.get('plan_file')
    state_file = module.params.get('state_file')
    force_init = module.params.get('force_init')
    backend_config = module.params.get('backend_config')
    if bin_path is not None:
        command = [bin_path]
    else:
        command = [module.get_bin_path('terraform', required=True)]
    if force_init:
        init_plugins(command[0], project_path, backend_config)
    workspace_ctx = get_workspace_context(command[0], project_path)
    if workspace_ctx["current"] != workspace:
        if workspace not in workspace_ctx["all"]:
            create_workspace(command[0], project_path, workspace)
        else:
            select_workspace(command[0], project_path, workspace)
    if state == 'present':
        command.extend(APPLY_ARGS)
    elif state == 'absent':
        command.extend(DESTROY_ARGS)
    variables_args = []
    for k, v in variables.items():
        variables_args.extend([