fix: onepassword module resource naming and add demo screenshot (#827)

Fixes `coder_script "1password"` → `coder_script "onepassword"` since
Terraform resource names cannot start with a digit. Adds a demo
screenshot showing the template variables page and `op whoami` working
in a workspace. Bumps version to 1.0.2.

Author: bpmct

registry/bpmct/.images/onepassword-demo.png

@@ -14,10 +14,12 @@ account token. Can also install the
 [1Password VS Code extension](https://marketplace.visualstudio.com/items?itemName=1Password.op-vscode)
 for code-server and VS Code.
 
+![1Password module in Coder](../../.images/onepassword-demo.png)
+
 ```tf
 module "onepassword" {
   source                = "registry.coder.com/bpmct/onepassword/coder"
-  version               = "1.0.1"
+  version               = "1.0.2"
   agent_id              = coder_agent.main.id
   service_account_token = var.op_service_account_token
 }
@@ -40,7 +42,7 @@ variable "op_service_account_token" {
 
 module "onepassword" {
   source                = "registry.coder.com/bpmct/onepassword/coder"
-  version               = "1.0.1"
+  version               = "1.0.2"
   agent_id              = coder_agent.main.id
   service_account_token = var.op_service_account_token
 }
@@ -55,7 +57,7 @@ terminal.
 ```tf
 module "onepassword" {
   source             = "registry.coder.com/bpmct/onepassword/coder"
-  version            = "1.0.1"
+  version            = "1.0.2"
   agent_id           = coder_agent.main.id
   account_address    = "myteam.1password.com"
   account_email      = "you@example.com"
@@ -71,7 +73,7 @@ for code-server and VS Code.
 ```tf
 module "onepassword" {
   source                   = "registry.coder.com/bpmct/onepassword/coder"
-  version                  = "1.0.1"
+  version                  = "1.0.2"
   agent_id                 = coder_agent.main.id
   service_account_token    = var.op_service_account_token
   install_vscode_extension = true
@@ -85,7 +87,7 @@ Run custom logic before or after the CLI is installed.
 ```tf
 module "onepassword" {
   source                = "registry.coder.com/bpmct/onepassword/coder"
-  version               = "1.0.1"
+  version               = "1.0.2"
   agent_id              = coder_agent.main.id
   service_account_token = var.op_service_account_token
   post_install_script   = <<-EOT

registry/bpmct/modules/onepassword/README.md

@@ -84,7 +84,7 @@ data "coder_parameter" "account_password" {
   default      = ""
 }
 
-resource "coder_script" "1password" {
+resource "coder_script" "onepassword" {
   agent_id     = var.agent_id
   display_name = "1Password CLI"
   icon         = "/icon/1password.svg"