Use isolated flag when gathering environment information (microsoft#20403)

Closes microsoft#20382

Author: Kartik Raj

src/client/pythonEnvironments/base/info/environmentInfoService.ts

@@ -38,7 +38,7 @@ export interface IEnvironmentInfoService {
 }
 
 async function buildEnvironmentInfo(env: PythonEnvInfo): Promise<InterpreterInformation | undefined> {
-    const python = [env.executable.filename, OUTPUT_MARKER_SCRIPT];
+    const python = [env.executable.filename, '-I', OUTPUT_MARKER_SCRIPT];
     const interpreterInfo = await getInterpreterInfo(buildPythonExecInfo(python, undefined, env.executable.filename));
     return interpreterInfo;
 }
@@ -50,7 +50,7 @@ async function buildEnvironmentInfoUsingCondaRun(env: PythonEnvInfo): Promise<In
     if (!condaEnv) {
         return undefined;
     }
-    const python = await conda?.getRunPythonArgs(condaEnv, true);
+    const python = await conda?.getRunPythonArgs(condaEnv, true, true);
     if (!python) {
         return undefined;
     }

src/client/pythonEnvironments/common/environmentManagers/conda.ts

@@ -506,7 +506,11 @@ export class Conda {
         return 'python';
     }
 
-    public async getRunPythonArgs(env: CondaEnvInfo, forShellExecution?: boolean): Promise<string[] | undefined> {
+    public async getRunPythonArgs(
+        env: CondaEnvInfo,
+        forShellExecution?: boolean,
+        isolatedFlag = false,
+    ): Promise<string[] | undefined> {
         const condaVersion = await this.getCondaVersion();
         if (condaVersion && lt(condaVersion, CONDA_RUN_VERSION)) {
             traceError('`conda run` is not supported for conda version', condaVersion.raw);
@@ -518,14 +522,17 @@ export class Conda {
         } else {
             args.push('-p', env.prefix);
         }
-        return [
+        const python = [
             forShellExecution ? this.shellCommand : this.command,
             'run',
             ...args,
             '--no-capture-output',
             'python',
-            OUTPUT_MARKER_SCRIPT,
         ];
+        if (isolatedFlag) {
+            python.push('-I');
+        }
+        return [...python, OUTPUT_MARKER_SCRIPT];
     }
 
     /**