feat: Replace old page theme props with new ones

plugins/gcp-projects/src/components/NewProjectPage/NewProjectPage.tsx

@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+import { customPageTheme } from '@backstage/theme';
 import {
   Content,
   ContentHeader,
@@ -21,7 +22,6 @@ import {
   HeaderLabel,
   InfoCard,
   Page,
-  pageTheme,
   SimpleStepper,
   SimpleStepperStep,
   StructuredMetadataTable,
@@ -113,7 +113,7 @@ const labels = (
 
 export const NewProjectPage = () => {
   return (
-    <Page theme={pageTheme.service}>
+    <Page pageTheme={customPageTheme.pageTheme.service}>
       <Header title="New GCP Project" type="tool">
         {labels}
       </Header>

plugins/gcp-projects/src/components/ProjectDetailsPage/ProjectDetailsPage.tsx

@@ -13,14 +13,13 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
+import { customPageTheme } from '@backstage/theme';
 import {
   Content,
   ContentHeader,
   Header,
   HeaderLabel,
   Page,
-  pageTheme,
   SupportButton,
   useApi,
   WarningPanel,
@@ -149,7 +148,7 @@ const labels = (
 
 export const ProjectDetailsPage = () => {
   return (
-    <Page theme={pageTheme.service}>
+    <Page pageTheme={customPageTheme.pageTheme.service}>
       <Header title="GCP Project Details" type="other">
         {labels}
       </Header>

plugins/gcp-projects/src/components/ProjectListPage/ProjectListPage.tsx

@@ -15,7 +15,7 @@
  */
 
 //  NEEDS WORK
-
+import { customPageTheme } from '@backstage/theme';
 import {
   Content,
   ContentHeader,
@@ -23,7 +23,6 @@ import {
   HeaderLabel,
   Link,
   Page,
-  pageTheme,
   SupportButton,
   useApi,
   WarningPanel,
@@ -136,7 +135,7 @@ const PageContents = () => {
 
 export const ProjectListPage = () => {
   return (
-    <Page theme={pageTheme.service}>
+    <Page pageTheme={customPageTheme.pageTheme.service}>
       <Header title="GCP Projects" type="tool">
         {labels}
       </Header>