Revert "PODMAN_USE_NAMESPACES to disable using namespaces on podman i…

…ntegration tests for podman v4.5 (redhat-developer#6774)"

We'll completely remove the usage of namespaces in the tests, as this
wad removed from Podman v4.5.0, because namespaces on Podman were
reportedly not really working [1].

This reverts commit ef9206a.

[1]
containers/podman@c4fe0af

docs/website/docs/overview/configure.md

@@ -191,7 +191,5 @@ Options here are mostly used for debugging and testing `odo` behavior.
 | `TELEMETRY_CALLER`         | Caller identifier passed to [telemetry](https://github.com/redhat-developer/odo/blob/main/USAGE_DATA.md). Case-insensitive. Acceptable values: `vscode`, `intellij`, `jboss`.                                                                                                                                                                                                  | v3.1.0        | `intellij`                      |
 | `ODO_TRACKING_CONSENT`     | Useful for controlling [telemetry](https://github.com/redhat-developer/odo/blob/main/USAGE_DATA.md). Acceptable values: `yes` ([enables telemetry](https://github.com/redhat-developer/odo/blob/main/USAGE_DATA.md) and skips consent prompt), `no` (disables telemetry and consent prompt). Takes precedence over the [`ConsentTelemetry`](#preference-key-table) preference. | v3.2.0        | `yes`                           |
 | `ODO_PUSH_IMAGES`          | Whether to push the images once built; this is used only when applying Devfile image components as part of a Dev Session running on Podman; this is useful for integration tests running on Podman. `true` by default                                                                                                                     | v3.7.0        | `false`                         |
-| `PODMAN_USE_NAMESPACES`          | Whether to isolate pods on namespaces when running integration tests on Podman. `true` by default                                                                                                                     | v3.10.0        | `false`                         |
-
 
 (1) Accepted boolean values are: `1`, `t`, `T`, `TRUE`, `true`, `True`, `0`, `f`, `F`, `FALSE`, `false`, `False`.

tests/helper/helper_podman.go

@@ -7,27 +7,13 @@ import (
 	"os/exec"
 	"path/filepath"
 	"regexp"
-	"strconv"
 	"strings"
 
 	. "github.com/onsi/gomega"
 	"github.com/redhat-developer/odo/pkg/podman"
 )
 
-func getBooleanValueFromEnvVar(envvar string, defaultValue bool) bool {
-	strVal := os.Getenv("PODMAN_USE_NAMESPACES")
-	boolValue, err := strconv.ParseBool(strVal)
-	if err != nil {
-		return defaultValue
-	}
-	return boolValue
-}
-
 func GenerateAndSetContainersConf(dir string) {
-	useNamespaces := getBooleanValueFromEnvVar("PODMAN_USE_NAMESPACES", true)
-	if !useNamespaces {
-		return
-	}
 	ns := GetProjectName()
 	containersConfPath := filepath.Join(dir, "containers.conf")
 	err := CreateFileWithContent(containersConfPath, fmt.Sprintf(`